diff --git a/app/Makefile b/app/Makefile
index a4c3b312..f18ee9ff 100644
--- a/app/Makefile
+++ b/app/Makefile
@@ -198,12 +198,14 @@ ZSV=$(BINDIR)/zsv${EXE}
 SOURCES=echo paste count count-pull select select-pull 2tsv 2json serialize flatten pretty stack desc sql 2db compare prop rm mv jq overwrite
 CLI_SOURCES=echo select desc count paste 2tsv pretty sql flatten 2json serialize stack 2db compare prop rm mv jq overwrite
 
+SHEET_INCLUDES=
 ifeq ($(ZSVSHEET_BUILD),1)
   SOURCES+=sheet
   CLI_SOURCES+=sheet
   CFLAGS+=-DZSVSHEET_BUILD
   CFLAGS+=${CFLAGS_NCURSES}
   LDFLAGS+=${LDFLAGS_NCURSES}
+  SHEET_INCLUDES=$(wildcard sheet/*.c sheet/*.h)
 endif
 
 CFLAGS+= -DUSE_JQ
@@ -285,6 +287,8 @@ SQLITE_SRC=${THIS_MAKEFILE_DIR}/external/sqlite3/sqlite3*.c
 SQLITE_EXT=${BUILD_DIR}-external/sqlite3/sqlite3_and_csv_vtab.o
 SQLITE_EXT_INCLUDE=-I${THIS_MAKEFILE_DIR}/external/sqlite3
 
+SQL_INTERNAL_OBJECT=${CLI_OBJ_PFX}sql_internal.o
+
 # everything uses prop, which in turn uses yajl and jq and json and sqlite3
 OBJECTS+= ${YAJL_OBJ} ${YAJL_HELPER_OBJ} ${BUILD_DIR}/objs/utils/json.o ${SQLITE_EXT}
 MORE_SOURCE+= ${YAJL_INCLUDE} ${YAJL_HELPER_INCLUDE} -I${JQ_INCLUDE_DIR} ${SQLITE_EXT_INCLUDE}
@@ -398,12 +402,18 @@ ${INIH_OBJECT}: ${INIH_SRC}/ini.c
 	@mkdir -p `dirname "$@"`
 	${CC} ${CFLAGS} -I${INIH_INCLUDE} -DINI_HANDLER_LINENO=1 -DINI_CALL_HANDLER_ON_NEW_SECTION=1 -c $< -o $@
 
+${SQL_INTERNAL_OBJECT}: ${CLI_OBJ_PFX}%.o: %.c %.h
+	@mkdir -p `dirname "$@"`
+	${CC} ${CFLAGS} -I${INCLUDE_DIR} -c -o $@ $<
+
+${CLI_OBJ_PFX}sheet.o: ${SHEET_INCLUDES}
+
 ${CLI_APP_OBJECT} : cli_ini.c builtin/*.c ${JQ_LIB}
 ${CLI_APP_OBJECT} ${CLI_OBJECTS}: ${CLI_OBJ_PFX}%.o: %.c ${UTF8PROC_SRC}/utf8proc.c # ${MORE_OBJECTS}
 	@mkdir -p `dirname "$@"`
 	${CC} ${CFLAGS} -DVERSION=\"${VERSION}\" -DZSV_CLI ${CLI_INCLUDE} -I${THIS_MAKEFILE_DIR}/external/sglib -I${INCLUDE_DIR} -I${UTF8PROC_INCLUDE} -c $< -o $@ ${MORE_SOURCE}
 
-${CLI}: cli_internal.c.in cli_internal.h cli_internal.h.in ${CLI_APP_OBJECT} ${CLI_OBJECTS} ${OBJECTS} ${UTF8PROC_OBJECT} cli_ini.c ${INIH_OBJECT} ${LIBZSV_INSTALL} ${MORE_OBJECTS}
+${CLI}: cli_internal.c.in cli_internal.h cli_internal.h.in ${CLI_APP_OBJECT} ${CLI_OBJECTS} ${OBJECTS} ${UTF8PROC_OBJECT} cli_ini.c ${INIH_OBJECT} ${LIBZSV_INSTALL} ${MORE_OBJECTS} ${SQL_INTERNAL_OBJECT}
 	@mkdir -p `dirname "$@"`
 	${CC} ${CFLAGS} ${CFLAGS_EXE} -I${INCLUDE_DIR} -o $@ ${CLI_APP_OBJECT} ${CLI_OBJECTS} ${OBJECTS} ${UTF8PROC_OBJECT} ${INIH_OBJECT} -L${LIBDIR} ${LIBZSV_L} ${LDFLAGS} ${LDFLAGS_OPT} ${MORE_OBJECTS} ${MORE_SOURCE} ${MORE_LIBS} ${STATIC_LIB_FLAGS}
 	@echo Built $@
@@ -468,6 +478,10 @@ ${CLI} ${STANDALONE_PFX}2json${EXE}: MORE_OBJECTS+= ${BUILD_DIR}/objs/utils/db.o
 # pretty uses termcap
 ${CLI} ${STANDALONE_PFX}pretty${EXE}: MORE_LIBS+=${LDFLAGS_TERMCAP}
 
+${STANDALONE_PFX}sheet${EXE}: ${SHEET_INCLUDES}
+
+${CLI} ${STANDALONE_PFX}sheet${EXE} ${STANDALONE_PFX}sql${EXE}: ${SQL_INTERNAL_OBJECT}
+${CLI} ${STANDALONE_PFX}sheet${EXE} ${STANDALONE_PFX}sql${EXE}: MORE_OBJECTS+=${SQL_INTERNAL_OBJECT}
 
 ${STANDALONE_PFX}%${EXE}: %.c ${OBJECTS} ${MORE_OBJECTS} ${LIBZSV_INSTALL} ${UTF8PROC_OBJECT}
 	@mkdir -p `dirname "$@"`
diff --git a/app/cli.c b/app/cli.c
index cc71173b..1bd187f6 100644
--- a/app/cli.c
+++ b/app/cli.c
@@ -419,6 +419,7 @@ static struct zsv_ext_callbacks *zsv_ext_callbacks_init(struct zsv_ext_callbacks
     e->ext_sheet_buffer_filename = zsvsheet_buffer_filename;
     e->ext_sheet_buffer_data_filename = zsvsheet_buffer_data_filename;
     e->ext_sheet_open_file = zsvsheet_open_file;
+    e->ext_sheet_open_file_opts = zsvsheet_ext_open_file_opts;
     e->ext_sheet_register_proc = zsvsheet_register_proc;
     e->ext_sheet_register_proc_key_binding = zsvsheet_register_proc_key_binding;
     e->ext_sheet_push_transformation = zsvsheet_push_transformation;
diff --git a/app/ext_example/mysheet_extension.c b/app/ext_example/mysheet_extension.c
index 2111572c..60d31d01 100644
--- a/app/ext_example/mysheet_extension.c
+++ b/app/ext_example/mysheet_extension.c
@@ -189,9 +189,12 @@ static zsvsheet_status zsv_sqlite3_to_csv(zsvsheet_proc_context_t pctx, struct z
     if (writer_opts.stream)
       fclose(writer_opts.stream);
 
-    if (tmp_fn && zsv_file_exists(tmp_fn))
-      zst = zsv_cb.ext_sheet_open_file(pctx, tmp_fn, NULL);
-    else {
+    if (tmp_fn && zsv_file_exists(tmp_fn)) {
+      struct zsvsheet_open_file_opts ofopts = {0};
+      ofopts.data_filename = tmp_fn;
+      ofopts.no_auto_row_num = 1;
+      zst = zsv_cb.ext_sheet_open_file_opts(pctx, &ofopts);
+    } else {
       if (zst == zsvsheet_status_ok) {
         zst = zsvsheet_status_error; // to do: make this more specific
         if (!err_msg && zdb && zdb->rc != SQLITE_OK)
@@ -229,12 +232,9 @@ zsvsheet_status pivot_drill_down(zsvsheet_proc_context_t ctx) {
     if (!zdb || !(sql_str = sqlite3_str_new(zdb->db)))
       zst = zsvsheet_status_memory;
     else if (zdb->rc == SQLITE_OK && zsv_cb.ext_sqlite3_add_csv(zdb, pd->data_filename, NULL, NULL) == SQLITE_OK) {
-      if (zsv_cb.ext_sheet_buffer_info(buff).has_row_num)
-        sqlite3_str_appendf(sql_str, "select *");
-      else
-        sqlite3_str_appendf(sql_str, "select rowid as [Row #], *");
+      sqlite3_str_appendf(sql_str, "select rowid as [Row #], *");
       sqlite3_str_appendf(sql_str, " from data where %s = %Q", pd->value_sql, pr->value);
-      fprintf(stderr, "SQL: %s\n", sqlite3_str_value(sql_str));
+      // fprintf(stderr, "SQL: %s\n", sqlite3_str_value(sql_str));
       zst = zsv_sqlite3_to_csv(ctx, zdb, sqlite3_str_value(sql_str), NULL, NULL, NULL);
     }
     if (sql_str)
@@ -327,7 +327,7 @@ enum zsv_ext_status zsv_ext_init(struct zsv_ext_callbacks *cb, zsv_execution_con
   int proc_id = zsv_cb.ext_sheet_register_proc("my-sheet-pivot", "my sheet pivot", my_pivot_table_command_handler);
   if (proc_id < 0)
     return zsv_ext_status_error;
-  zsv_cb.ext_sheet_register_proc_key_binding('v', proc_id);
+  zsv_cb.ext_sheet_register_proc_key_binding('s', proc_id);
   return zsv_ext_status_ok;
 }
 
diff --git a/app/sheet.c b/app/sheet.c
index a34ed39d..ab10f77c 100644
--- a/app/sheet.c
+++ b/app/sheet.c
@@ -49,8 +49,8 @@ struct zsvsheet_opts {
 #define ZSVSHEET_CELL_DISPLAY_MIN_WIDTH 10
 static size_t zsvsheet_cell_display_width(struct zsvsheet_ui_buffer *ui_buffer,
                                           struct zsvsheet_display_dimensions *ddims) {
-  size_t width = ddims->columns /
-                 (ui_buffer->dimensions.col_count + (ui_buffer->rownum_col_offset && !ui_buffer->has_row_num ? 1 : 0));
+  size_t width = ddims->columns / (ui_buffer->dimensions.col_count +
+                                   (ui_buffer->rownum_col_offset && !ui_buffer->no_add_row_num ? 1 : 0));
   return width < ZSVSHEET_CELL_DISPLAY_MIN_WIDTH ? ZSVSHEET_CELL_DISPLAY_MIN_WIDTH : width;
 }
 
@@ -166,7 +166,8 @@ size_t display_data_rowcount(struct zsvsheet_display_dimensions *dims) {
   return dims->rows - dims->footer_span - dims->header_span;
 }
 
-char zsvsheet_status_text[256] = {0};
+static int zsvsheet_status_priority;
+static char zsvsheet_status_text[256];
 static void zsvsheet_display_status_text(const struct zsvsheet_display_dimensions *ddims) {
   // clear the entire line
   mvprintw(ddims->rows - ddims->footer_span, 0, "%-*s", (int)sizeof(zsvsheet_status_text), "");
@@ -177,15 +178,24 @@ static void zsvsheet_display_status_text(const struct zsvsheet_display_dimension
   attroff(A_REVERSE);
 }
 
-static void zsvsheet_priv_set_status(const struct zsvsheet_display_dimensions *ddims, int overwrite, const char *fmt,
+#define ZSVSHEET_STATUS_LOW_PRIO 1
+#define ZSVSHEET_STATUS_HIGH_PRIO 10
+
+static void zsvsheet_priv_set_status(const struct zsvsheet_display_dimensions *ddims, int priority, const char *fmt,
                                      ...) {
-  if (overwrite || !*zsvsheet_status_text) {
+  if (priority > zsvsheet_status_priority || !*zsvsheet_status_text) {
     va_list argv;
     va_start(argv, fmt);
     vsnprintf(zsvsheet_status_text, sizeof(zsvsheet_status_text), fmt, argv);
     va_end(argv);
     // note: if (n < (int)sizeof(zsvsheet_status_text)), then we just ignore
+    zsvsheet_status_priority = priority;
   }
+
+  // The priority decays with each call which is at least n times per second as set by halfdelay
+  if (zsvsheet_status_priority > 0)
+    zsvsheet_status_priority--;
+
   zsvsheet_display_status_text(ddims);
 }
 
@@ -331,7 +341,7 @@ char zsvsheet_handle_find_next(struct zsvsheet_ui_buffer *uib, const char *needl
     *update_buffer = zsvsheet_goto_input_raw_row(uib, zsvsheet_opts->found_rownum, header_span, ddims, (size_t)-1);
     return 1;
   }
-  zsvsheet_priv_set_status(ddims, 1, "Not found");
+  zsvsheet_priv_set_status(ddims, ZSVSHEET_STATUS_HIGH_PRIO, "Not found");
   return 0;
 }
 
@@ -394,11 +404,11 @@ static zsvsheet_status zsvsheet_open_file_handler(struct zsvsheet_proc_context *
   if ((err = zsvsheet_ui_buffer_open_file(filename, NULL, state->custom_prop_handler, di->ui_buffers.base,
                                           di->ui_buffers.current))) {
     if (err > 0)
-      zsvsheet_priv_set_status(di->dimensions, 1, "%s: %s", filename, strerror(err));
+      zsvsheet_priv_set_status(di->dimensions, ZSVSHEET_STATUS_HIGH_PRIO, "%s: %s", filename, strerror(err));
     else if (err < 0)
-      zsvsheet_priv_set_status(di->dimensions, 1, "Unexpected error");
+      zsvsheet_priv_set_status(di->dimensions, ZSVSHEET_STATUS_HIGH_PRIO, "Unexpected error");
     else
-      zsvsheet_priv_set_status(di->dimensions, 1, "Not found: %s", filename);
+      zsvsheet_priv_set_status(di->dimensions, ZSVSHEET_STATUS_HIGH_PRIO, "Not found: %s", filename);
     return zsvsheet_status_ignore;
   }
 no_input:
@@ -462,16 +472,17 @@ static zsvsheet_status zsvsheet_help_handler(struct zsvsheet_proc_context *ctx)
   struct zsvsheet_sheet_context *state = (struct zsvsheet_sheet_context *)ctx->subcommand_context;
   struct zsvsheet_display_info *di = &state->display_info;
   struct zsvsheet_screen_buffer_opts bopts = {
-    .no_rownum_column = 1,
     .cell_buff_len = 64,
     .max_cell_len = 0,
     .rows = 256,
   };
+  struct zsvsheet_opts zsvsheet_opts = {0};
+  zsvsheet_opts.hide_row_nums = 1;
   struct zsvsheet_ui_buffer_opts uibopts = {
+    .zsvsheet_opts = &zsvsheet_opts,
     .buff_opts = &bopts,
     .filename = NULL,
     .data_filename = NULL,
-    .no_rownum_col_offset = 1,
     .write_after_open = 0,
   };
   struct zsvsheet_ui_buffer *uib = NULL;
@@ -538,6 +549,7 @@ static zsvsheet_status zsvsheet_help_handler(struct zsvsheet_proc_context *ctx)
   return stat;
 }
 
+#include "sheet/pivot.c"
 #include "sheet/newline_handler.c"
 
 /* We do most procedures in one handler. More complex procedures can be
@@ -624,7 +636,9 @@ struct builtin_proc_desc {
   { zsvsheet_builtin_proc_filter,         "filter", "Hide rows that do not contain the specified text",                zsvsheet_filter_handler       },
   { zsvsheet_builtin_proc_subcommand,     "subcommand",  "Editor subcommand",                                          zsvsheet_subcommand_handler },
   { zsvsheet_builtin_proc_help,           "help",   "Display a list of actions and key-bindings",                      zsvsheet_help_handler         },
-  { zsvsheet_builtin_proc_newline,        "<Enter>","Follow hyperlink (if any)",                                       zsvsheet_newline_handler      },
+  { zsvsheet_builtin_proc_newline,        "<Enter>","Follow hyperlink (if any) or drill down",                         zsvsheet_newline_handler      },
+  { zsvsheet_builtin_proc_pivot_cur_col,  "pivotcur","Group rows by the column under the cursor",                      zsvsheet_pivot_handler        },
+  { zsvsheet_builtin_proc_pivot_expr,     "pivotexpr","Group rows with group-by SQL expression",                       zsvsheet_pivot_handler        },
   { -1, NULL, NULL, NULL }
 };
 /* clang-format on */
@@ -642,7 +656,7 @@ static void zsvsheet_check_buffer_worker_updates(struct zsvsheet_ui_buffer *ub,
                                                  struct zsvsheet_sheet_context *handler_state) {
   pthread_mutex_lock(&ub->mutex);
   if (ub->status)
-    zsvsheet_priv_set_status(display_dims, 1, ub->status);
+    zsvsheet_priv_set_status(display_dims, ZSVSHEET_STATUS_LOW_PRIO, ub->status);
   if (ub->index_ready && ub->dimensions.row_count != ub->index->row_count + 1) {
     ub->dimensions.row_count = ub->index->row_count + 1;
     handler_state->display_info.update_buffer = true;
@@ -738,7 +752,7 @@ int ZSV_MAIN_FUNC(ZSV_COMMAND)(int argc, const char *argv[], struct zsv_opts *op
     ch = getch();
 
     handler_state.display_info.update_buffer = false;
-    zsvsheet_priv_set_status(&display_dims, 1, "");
+    zsvsheet_priv_set_status(&display_dims, ZSVSHEET_STATUS_LOW_PRIO, "");
 
     if (ch != ERR) {
       status = zsvsheet_key_press(ch, &handler_state);
@@ -753,9 +767,12 @@ int ZSV_MAIN_FUNC(ZSV_COMMAND)(int argc, const char *argv[], struct zsv_opts *op
 
     if (handler_state.display_info.update_buffer && zsvsheet_buffer_data_filename(ub)) {
       struct zsvsheet_opts zsvsheet_opts = {0};
-      if (read_data(&ub, NULL, current_ui_buffer->input_offset.row, current_ui_buffer->input_offset.col, header_span,
-                    &zsvsheet_opts, custom_prop_handler)) {
-        zsvsheet_priv_set_status(&display_dims, 1, "Unexpected error!"); // to do: better error message
+      struct zsvsheet_ui_buffer_opts uibopts = {0};
+      uibopts.zsvsheet_opts = &zsvsheet_opts;
+      if (read_data(&ub, &uibopts, current_ui_buffer->input_offset.row, current_ui_buffer->input_offset.col,
+                    header_span, custom_prop_handler)) {
+        zsvsheet_priv_set_status(&display_dims, ZSVSHEET_STATUS_HIGH_PRIO,
+                                 "Unexpected error!"); // to do: better error message
         continue;
       }
     }
diff --git a/app/sheet/file.c b/app/sheet/file.c
index 5e4122e9..81aceadd 100644
--- a/app/sheet/file.c
+++ b/app/sheet/file.c
@@ -1,3 +1,5 @@
+#include <zsv/ext/sheet.h>
+
 int zsvsheet_ui_buffer_open_file_opts(struct zsvsheet_ui_buffer_opts *uibopts,
                                       struct zsv_prop_handler *custom_prop_handler,
                                       struct zsvsheet_ui_buffer **ui_buffer_stack_bottom,
@@ -6,11 +8,14 @@ int zsvsheet_ui_buffer_open_file_opts(struct zsvsheet_ui_buffer_opts *uibopts,
   struct zsvsheet_screen_buffer_opts bopts = {0};
   struct zsvsheet_ui_buffer *tmp_ui_buffer = NULL;
 
+  if (!uibopts->zsvsheet_opts)
+    uibopts->zsvsheet_opts = &zsvsheet_opts;
+
   if (!uibopts->buff_opts)
     uibopts->buff_opts = &bopts;
 
   int err = 0;
-  if ((err = read_data(&tmp_ui_buffer, uibopts, 0, 0, 0, &zsvsheet_opts, custom_prop_handler)) != 0 || !tmp_ui_buffer ||
+  if ((err = read_data(&tmp_ui_buffer, uibopts, 0, 0, 0, custom_prop_handler)) != 0 || !tmp_ui_buffer ||
       !tmp_ui_buffer->buff_used_rows) {
     zsvsheet_ui_buffer_delete(tmp_ui_buffer);
     if (err)
@@ -62,3 +67,17 @@ zsvsheet_status zsvsheet_open_file_opts(struct zsvsheet_proc_context *ctx, struc
     return zsvsheet_status_error;
   return zsvsheet_status_ok;
 }
+
+zsvsheet_status zsvsheet_ext_open_file_opts(struct zsvsheet_proc_context *ctx, struct zsvsheet_open_file_opts *opts) {
+  struct zsvsheet_ui_buffer_opts uibopts = {0};
+  struct zsvsheet_opts zsvsheet_opts = {0};
+
+  zsvsheet_opts.hide_row_nums = opts->no_auto_row_num;
+  uibopts.zsvsheet_opts = &zsvsheet_opts;
+  uibopts.filename = opts->filename;
+  uibopts.data_filename = opts->data_filename;
+  if (opts->zsv_opts)
+    uibopts.zsv_opts = *opts->zsv_opts;
+
+  return zsvsheet_open_file_opts(ctx, &uibopts);
+}
diff --git a/app/sheet/file.h b/app/sheet/file.h
index 482db958..d1df2227 100644
--- a/app/sheet/file.h
+++ b/app/sheet/file.h
@@ -7,5 +7,6 @@ int zsvsheet_ui_buffer_open_file(const char *filename, const struct zsv_opts *zs
                                  struct zsvsheet_ui_buffer **ui_buffer_stack_top);
 
 zsvsheet_status zsvsheet_open_file_opts(struct zsvsheet_proc_context *ctx, struct zsvsheet_ui_buffer_opts *opts);
+zsvsheet_status zsvsheet_open_file(struct zsvsheet_proc_context *ctx, const char *filepath, struct zsv_opts *zopts);
 
 #endif
diff --git a/app/sheet/handlers.c b/app/sheet/handlers.c
index 4b6306c8..c3a3dd97 100644
--- a/app/sheet/handlers.c
+++ b/app/sheet/handlers.c
@@ -45,6 +45,7 @@ zsvsheet_status zsvsheet_set_status(struct zsvsheet_proc_context *ctx, const cha
   va_end(argv);
   // note: if (n < (int)sizeof(zsvsheet_status_text)), then we just ignore
   zsvsheet_display_status_text(state->display_info.dimensions);
+  zsvsheet_status_priority = ZSVSHEET_STATUS_HIGH_PRIO;
   return zsvsheet_status_ok;
 }
 
@@ -112,7 +113,7 @@ zsvsheet_status zsvsheet_buffer_get_selected_cell(zsvsheet_buffer_t h, struct zs
   if (!uib)
     return zsvsheet_status_error;
   rc->row = uib->cursor_row + uib->input_offset.row + uib->buff_offset.row;
-  rc->col = uib->cursor_col + uib->input_offset.col + uib->buff_offset.row;
+  rc->col = uib->cursor_col + uib->input_offset.col + uib->buff_offset.col;
   return zsvsheet_status_ok;
 }
 
@@ -191,7 +192,7 @@ struct zsvsheet_buffer_data zsvsheet_buffer_info(zsvsheet_buffer_t h) {
   struct zsvsheet_buffer_data d = {0};
   struct zsvsheet_ui_buffer *b = h;
   if (b) {
-    d.has_row_num = b->has_row_num;
+    d.has_row_num = b->no_add_row_num;
   }
   return d;
 }
diff --git a/app/sheet/handlers_internal.h b/app/sheet/handlers_internal.h
index b639fe45..975007de 100644
--- a/app/sheet/handlers_internal.h
+++ b/app/sheet/handlers_internal.h
@@ -1,6 +1,8 @@
 #ifndef ZSVSHEET_HANDLER_INTERNAL_H
 #define ZSVSHEET_HANDLER_INTERNAL_H
 
+#include <zsv/ext.h>
+
 struct zsvsheet_context {
   const char *subcommand_value; // e.g. "/path/to/myfile.csv"
   int ch;                       // key press value from getch()
@@ -34,6 +36,11 @@ zsvsheet_status zsvsheet_open_file(struct zsvsheet_proc_context *ctx, const char
 
 /** extension support **/
 
+/**
+ * Open a tabular file with external facing options
+ */
+zsvsheet_status zsvsheet_ext_open_file_opts(struct zsvsheet_proc_context *ctx, struct zsvsheet_open_file_opts *opts);
+
 /**
  * Set the subcommand prompt
  */
diff --git a/app/sheet/key-bindings.c b/app/sheet/key-bindings.c
index c1b5bdc7..6eff5049 100644
--- a/app/sheet/key-bindings.c
+++ b/app/sheet/key-bindings.c
@@ -174,6 +174,8 @@ struct zsvsheet_key_binding zsvsheet_vim_key_bindings[] = {
   { .ch = '?',                 .proc_id = zsvsheet_builtin_proc_help,          },
   { .ch = '\n',                .proc_id = zsvsheet_builtin_proc_newline,       },
   { .ch = '\r',                .proc_id = zsvsheet_builtin_proc_newline,       },
+  { .ch = 'v',                 .proc_id = zsvsheet_builtin_proc_pivot_cur_col, },
+  { .ch = 'V',                 .proc_id = zsvsheet_builtin_proc_pivot_expr,    },
 
   { .ch = -1                                                          }
 };
diff --git a/app/sheet/pivot.c b/app/sheet/pivot.c
new file mode 100644
index 00000000..2819884d
--- /dev/null
+++ b/app/sheet/pivot.c
@@ -0,0 +1,317 @@
+/*
+ * Copyright (C) 2021 Liquidaty and zsv contributors. All rights reserved.
+ * This file is part of zsv/lib, distributed under the license defined at
+ * https://opensource.org/licenses/MIT
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include "../external/sqlite3/sqlite3.h"
+#include <zsv/ext/implementation.h>
+#include <zsv/ext/sheet.h>
+#include <zsv/utils/writer.h>
+#include <zsv/utils/file.h>
+#include <zsv/utils/prop.h>
+#include "file.h"
+#include "handlers_internal.h"
+#include "../sql_internal.h"
+
+struct pivot_row {
+  char *value; // to do: this will be the drill-down criteria
+};
+
+struct pivot_data {
+  char *value_sql; // the sql expression entered by the user e.g. City
+  char *data_filename;
+  struct zsv_opts zopts;
+  struct {
+    struct pivot_row *data; // for each row, the value of the sql expression e.g. New York
+    size_t capacity;
+    size_t used;
+  } rows;
+};
+
+static void pivot_data_delete(void *h) {
+  struct pivot_data *pd = h;
+  if (pd) {
+    for (size_t i = 0; i < pd->rows.used; i++)
+      free(pd->rows.data[i].value);
+    free(pd->rows.data);
+    free(pd->value_sql);
+    free(pd->data_filename);
+    free(pd);
+  }
+}
+
+static struct pivot_data *pivot_data_new(const char *data_filename, const char *value_sql) {
+  struct pivot_data *pd = calloc(1, sizeof(*pd));
+  if (pd && (pd->value_sql = strdup(value_sql)) && (pd->data_filename = strdup(data_filename)))
+    return pd;
+  pivot_data_delete(pd);
+  return NULL;
+}
+
+#define ZSV_MYSHEET_PIVOT_DATA_ROWS_INITIAL 32
+static int pivot_data_grow(struct pivot_data *pd) {
+  if (pd->rows.used == pd->rows.capacity) {
+    size_t new_capacity = pd->rows.capacity == 0 ? ZSV_MYSHEET_PIVOT_DATA_ROWS_INITIAL : pd->rows.capacity * 2;
+    struct pivot_row *new_data = realloc(pd->rows.data, new_capacity * sizeof(*pd->rows.data));
+    if (!new_data)
+      return ENOMEM;
+    pd->rows.data = new_data;
+    pd->rows.capacity = new_capacity;
+  }
+  return 0;
+}
+
+static int add_pivot_row(struct pivot_data *pd, const char *value, size_t len) {
+  int err = pivot_data_grow(pd);
+  char *value_dup = NULL;
+  if (!err && value && len) {
+    value_dup = malloc(len + 1);
+    if (value_dup) {
+      memcpy(value_dup, value, len);
+      value_dup[len] = '\0';
+    }
+  }
+  pd->rows.data[pd->rows.used++].value = value_dup;
+  return err;
+}
+
+static struct pivot_row *get_pivot_row_data(struct pivot_data *pd, size_t row_ix) {
+  if (pd && row_ix < pd->rows.used)
+    return &pd->rows.data[row_ix];
+  return NULL;
+}
+
+// TO DO: return zsvsheet_status
+static enum zsv_ext_status get_cell_attrs(void *pdh, zsvsheet_cell_attr_t *attrs, size_t start_row, size_t row_count,
+                                          size_t cols) {
+  struct pivot_data *pd = pdh;
+  size_t end_row = start_row + row_count;
+  int attr = 0;
+
+#ifdef A_BOLD
+  attr |= A_BOLD;
+#endif
+// Absent on Mac OSX 13
+#ifdef A_ITALIC
+  attr |= A_ITALIC;
+#endif
+
+  if (end_row > pd->rows.used)
+    end_row = pd->rows.used;
+  for (size_t i = start_row; i < end_row; i++)
+    attrs[i * cols] = attr;
+  return zsv_ext_status_ok;
+}
+
+static void pivot_on_header_cell(void *ctx, size_t col_ix, const char *colname) {
+  (void)colname;
+  if (col_ix == 0)
+    add_pivot_row(ctx, NULL, 0);
+}
+
+static void pivot_on_data_cell(void *ctx, size_t col_ix, const char *text, size_t len) {
+  if (col_ix == 0)
+    add_pivot_row(ctx, text, len);
+}
+
+static zsvsheet_status zsv_sqlite3_to_csv(zsvsheet_proc_context_t pctx, struct zsv_sqlite3_db *zdb, const char *sql,
+                                          void *ctx, void (*on_header_cell)(void *, size_t, const char *),
+                                          void (*on_data_cell)(void *, size_t, const char *, size_t len)) {
+  const char *err_msg = NULL;
+  zsvsheet_status zst = zsvsheet_status_error;
+  sqlite3_stmt *stmt = NULL;
+
+  if ((zdb->rc = sqlite3_prepare_v2(zdb->db, sql, -1, &stmt, NULL)) == SQLITE_OK) {
+    char *tmp_fn = zsv_get_temp_filename("zsv_mysheet_ext_XXXXXXXX");
+    struct zsv_csv_writer_options writer_opts = zsv_writer_get_default_opts();
+    zsv_csv_writer cw = NULL;
+    if (!tmp_fn)
+      zst = zsvsheet_status_memory;
+    else if (!(writer_opts.stream = fopen(tmp_fn, "wb"))) {
+      zst = zsvsheet_status_error;
+      err_msg = strerror(errno);
+    } else if (!(cw = zsv_writer_new(&writer_opts)))
+      zst = zsvsheet_status_memory;
+    else {
+      zst = zsvsheet_status_ok;
+      unsigned char cw_buff[1024];
+      zsv_writer_set_temp_buff(cw, cw_buff, sizeof(cw_buff));
+
+      int col_count = sqlite3_column_count(stmt);
+      // write header row
+      for (int i = 0; i < col_count; i++) {
+        const char *colname = sqlite3_column_name(stmt, i);
+        zsv_writer_cell(cw, !i, (const unsigned char *)colname, colname ? strlen(colname) : 0, 1);
+        if (on_header_cell)
+          on_header_cell(ctx, i, colname);
+      }
+
+      // write sql results
+      while (sqlite3_step(stmt) == SQLITE_ROW) {
+        for (int i = 0; i < col_count; i++) {
+          const unsigned char *text = sqlite3_column_text(stmt, i);
+          int len = text ? sqlite3_column_bytes(stmt, i) : 0;
+          zsv_writer_cell(cw, !i, text, len, 1);
+          if (on_data_cell)
+            on_data_cell(ctx, i, (const char *)text, len);
+        }
+      }
+    }
+    if (cw)
+      zsv_writer_delete(cw);
+    if (writer_opts.stream)
+      fclose(writer_opts.stream);
+
+    if (tmp_fn && zsv_file_exists(tmp_fn)) {
+      struct zsvsheet_opts zsvsheet_opts = {0};
+      zsvsheet_opts.hide_row_nums = 1;
+      struct zsvsheet_ui_buffer_opts uibopts = {0};
+      uibopts.zsvsheet_opts = &zsvsheet_opts;
+      uibopts.data_filename = tmp_fn;
+      zst = zsvsheet_open_file_opts(pctx, &uibopts);
+    } else {
+      if (zst == zsvsheet_status_ok) {
+        zst = zsvsheet_status_error; // to do: make this more specific
+        if (!err_msg && zdb && zdb->rc != SQLITE_OK)
+          err_msg = sqlite3_errmsg(zdb->db);
+      }
+    }
+    if (zst != zsvsheet_status_ok)
+      free(tmp_fn);
+  } else {
+    err_msg = sqlite3_errmsg(zdb->db);
+  }
+  if (stmt)
+    sqlite3_finalize(stmt);
+  if (err_msg)
+    zsvsheet_set_status(pctx, "Error: %s", err_msg);
+  return zst;
+}
+
+zsvsheet_status pivot_drill_down(zsvsheet_proc_context_t ctx) {
+  enum zsvsheet_status zst = zsvsheet_status_ok;
+  zsvsheet_buffer_t buff = zsvsheet_buffer_current(ctx);
+  struct pivot_data *pd;
+  struct zsvsheet_rowcol rc;
+  if (zsvsheet_buffer_get_ctx(buff, (void **)&pd) != zsv_ext_status_ok ||
+      zsvsheet_buffer_get_selected_cell(buff, &rc) != zsvsheet_status_ok) {
+    return zsvsheet_status_error;
+  }
+  struct pivot_row *pr = get_pivot_row_data(pd, rc.row);
+  if (pd && pd->data_filename && pd->value_sql && pr) {
+    struct zsv_sqlite3_dbopts dbopts = {0};
+    sqlite3_str *sql_str = NULL;
+    struct zsv_sqlite3_db *zdb = zsv_sqlite3_db_new(&dbopts);
+
+    if (!zdb || !(sql_str = sqlite3_str_new(zdb->db)))
+      zst = zsvsheet_status_memory;
+    else if (zdb->rc == SQLITE_OK && zsv_sqlite3_add_csv(zdb, pd->data_filename, &pd->zopts, NULL) == SQLITE_OK) {
+      sqlite3_str_appendf(sql_str, "select rowid as [Row #], * from data where %s = %Q", pd->value_sql, pr->value);
+      zst = zsv_sqlite3_to_csv(ctx, zdb, sqlite3_str_value(sql_str), NULL, NULL, NULL);
+    }
+
+    if (sql_str)
+      sqlite3_free(sqlite3_str_finish(sql_str));
+    if (zdb) {
+      if (zst != zsvsheet_status_ok) {
+        // to do: consolidate this with same code in sql.c
+        if (zdb->err_msg)
+          fprintf(stderr, "Error: %s\n", zdb->err_msg);
+        else if (!zdb->db)
+          fprintf(stderr, "Error (unable to open db, code %i): %s\n", zdb->rc, sqlite3_errstr(zdb->rc));
+        else if (zdb->rc != SQLITE_OK)
+          fprintf(stderr, "Error (code %i): %s\n", zdb->rc, sqlite3_errstr(zdb->rc));
+      }
+      zsv_sqlite3_db_delete(zdb);
+    }
+  }
+  return zst;
+}
+
+/**
+ * Here we define a custom command for the zsv `sheet` feature
+ */
+static zsvsheet_status zsvsheet_pivot_handler(struct zsvsheet_proc_context *ctx) {
+  char result_buffer[256] = {0};
+  const char *expr;
+  size_t trim_len;
+  struct zsvsheet_rowcol rc;
+  int ch = zsvsheet_ext_keypress(ctx);
+  if (ch < 0)
+    return zsvsheet_status_error;
+
+  zsvsheet_buffer_t buff = zsvsheet_buffer_current(ctx);
+  const char *data_filename = NULL;
+  if (buff)
+    data_filename = zsvsheet_buffer_data_filename(buff);
+
+  if (!data_filename) { // TO DO: check that the underlying data is a tabular file and we know how to parse
+    zsvsheet_set_status(ctx, "Pivot table only available for tabular data buffers");
+    return zsvsheet_status_ok;
+  }
+
+  switch (ctx->proc_id) {
+  case zsvsheet_builtin_proc_pivot_expr:
+    zsvsheet_ext_prompt(ctx, result_buffer, sizeof(result_buffer), "Pivot table: Enter group-by SQL expr");
+    if (*result_buffer == '\0')
+      return zsvsheet_status_ok;
+    expr = result_buffer;
+    break;
+  case zsvsheet_builtin_proc_pivot_cur_col:
+    if (zsvsheet_buffer_get_selected_cell(buff, &rc) != zsvsheet_status_ok)
+      return zsvsheet_status_error;
+
+    expr = zsvsheet_ui_buffer_get_header(buff, rc.col);
+    assert(expr);
+    trim_len = strlen(expr);
+    expr = (char *)zsv_strtrim((unsigned char *)expr, &trim_len);
+    assert(expr);
+    assert(trim_len <= sizeof(result_buffer) - 1);
+    assert(trim_len > 0);
+    expr = sqlite3_snprintf(sizeof(result_buffer), result_buffer, "\"%.*w\"", trim_len, expr);
+    assert(strlen(expr) > trim_len);
+    break;
+  default:
+    assert(0);
+    return zsvsheet_status_error;
+  }
+
+  assert(strlen(expr) > 0);
+
+  enum zsvsheet_status zst = zsvsheet_status_ok;
+  struct zsv_sqlite3_dbopts dbopts = {0};
+  struct zsv_opts zopts = zsvsheet_buffer_get_zsv_opts(buff);
+  struct zsv_sqlite3_db *zdb = zsv_sqlite3_db_new(&dbopts);
+  sqlite3_str *sql_str = NULL;
+  struct pivot_data *pd = NULL;
+  if (!zdb || !(sql_str = sqlite3_str_new(zdb->db)))
+    zst = zsvsheet_status_memory;
+  else if (zdb->rc == SQLITE_OK && zsv_sqlite3_add_csv(zdb, data_filename, &zopts, NULL) == SQLITE_OK) {
+    sqlite3_str_appendf(sql_str, "select %s as value, count(1) as Count from data group by %s", expr, expr);
+    if (!(pd = pivot_data_new(data_filename, expr)))
+      zst = zsvsheet_status_memory;
+    else {
+      zst = zsv_sqlite3_to_csv(ctx, zdb, sqlite3_str_value(sql_str), pd, pivot_on_header_cell, pivot_on_data_cell);
+      if (zst == zsvsheet_status_ok) {
+        buff = zsvsheet_buffer_current(ctx);
+        zsvsheet_buffer_set_ctx(buff, pd, pivot_data_delete);
+        zsvsheet_buffer_set_cell_attrs(buff, get_cell_attrs);
+        zsvsheet_buffer_on_newline(buff, pivot_drill_down);
+        pd->zopts = zopts;
+        pd = NULL; // so that it isn't cleaned up below
+      }
+    }
+    // TO DO: add param to ext_sheet_open_file to set filename vs data_filename, and set buffer type or proc owner
+    // TO DO: add way to attach custom context, and custom context destructor, to the new buffer
+    // TO DO: add cell highlighting
+  }
+
+  zsv_sqlite3_db_delete(zdb);
+  if (sql_str)
+    sqlite3_free(sqlite3_str_finish(sql_str));
+  pivot_data_delete(pd);
+  return zst;
+}
diff --git a/app/sheet/procedure.h b/app/sheet/procedure.h
index 5c36a309..d81ac0c8 100644
--- a/app/sheet/procedure.h
+++ b/app/sheet/procedure.h
@@ -34,6 +34,8 @@ enum {
   zsvsheet_builtin_proc_help,
   zsvsheet_builtin_proc_vim_g_key_binding_dmux,
   zsvsheet_builtin_proc_newline,
+  zsvsheet_builtin_proc_pivot_expr,
+  zsvsheet_builtin_proc_pivot_cur_col,
 };
 
 #define ZSVSHEET_PROC_INVALID 0
diff --git a/app/sheet/read-data.c b/app/sheet/read-data.c
index f4878311..c8241d32 100644
--- a/app/sheet/read-data.c
+++ b/app/sheet/read-data.c
@@ -46,13 +46,13 @@ static void get_data_index_async(struct zsvsheet_ui_buffer *uibuffp, const char
 
 static int read_data(struct zsvsheet_ui_buffer **uibufferp,   // a new zsvsheet_ui_buffer will be allocated
                      struct zsvsheet_ui_buffer_opts *uibopts, // if *uibufferp == NULL and uibopts != NULL
-                     size_t start_row, size_t start_col, size_t header_span, struct zsvsheet_opts *zsvsheet_opts,
+                     size_t start_row, size_t start_col, size_t header_span,
                      struct zsv_prop_handler *custom_prop_handler) {
-  const char *filename = (uibufferp && *uibufferp) ? (*uibufferp)->filename : uibopts ? uibopts->filename : NULL;
+  struct zsvsheet_opts *zsvsheet_opts = uibopts->zsvsheet_opts;
   struct zsv_opts opts = {0};
   if (uibufferp && *uibufferp)
     opts = (*uibufferp)->zsv_opts;
-  else if (uibopts)
+  else
     opts = uibopts->zsv_opts;
 
   struct zsvsheet_ui_buffer *uibuff = uibufferp ? *uibufferp : NULL;
@@ -60,6 +60,7 @@ static int read_data(struct zsvsheet_ui_buffer **uibufferp,   // a new zsvsheet_
   size_t remaining_header_to_skip = header_span;
   size_t original_row_num = 0;
   FILE *fp;
+  const char *filename = NULL;
 
   if (uibuff) {
     if (uibuff->data_filename)
@@ -68,7 +69,7 @@ static int read_data(struct zsvsheet_ui_buffer **uibufferp,   // a new zsvsheet_
       filename = uibuff->filename;
   }
 
-  if (!filename && uibopts) {
+  if (!filename) {
     if (uibopts->data_filename)
       filename = uibopts->data_filename;
     else if (uibopts->filename)
@@ -116,17 +117,17 @@ static int read_data(struct zsvsheet_ui_buffer **uibufferp,   // a new zsvsheet_
   size_t find_len = zsvsheet_opts->find ? strlen(zsvsheet_opts->find) : 0;
   size_t rows_searched = 0;
   zsvsheet_screen_buffer_t buffer = uibuff ? uibuff->buffer : NULL;
-  if (uibuff && uibuff->has_row_num)
+  if (uibuff && uibuff->no_add_row_num)
     zsvsheet_opts->hide_row_nums = 1;
 
   while (zsv_next_row(parser) == zsv_status_row &&
          (rows_read == 0 || rows_read < zsvsheet_screen_buffer_rows(buffer))) { // for each row
 
     size_t col_count = zsv_cell_count(parser);
-    if (uibuff == NULL && uibufferp && uibopts && col_count > 0) {
+    if (uibuff == NULL && uibufferp && col_count > 0) {
       enum zsvsheet_priv_status stat;
       struct zsvsheet_ui_buffer *tmp_uibuff = NULL;
-      if (!(buffer = zsvsheet_screen_buffer_new(col_count, uibopts->buff_opts, &stat)) ||
+      if (!(buffer = zsvsheet_screen_buffer_new(col_count + 1, uibopts->buff_opts, &stat)) ||
           stat != zsvsheet_priv_status_ok || !(tmp_uibuff = zsvsheet_ui_buffer_new(buffer, uibopts))) {
         if (tmp_uibuff)
           zsvsheet_ui_buffer_delete(tmp_uibuff);
@@ -138,16 +139,16 @@ static int read_data(struct zsvsheet_ui_buffer **uibufferp,   // a new zsvsheet_
     }
 
     // row number
-    size_t rownum_column_offset = 0;
     if (rows_read == 0 && zsvsheet_opts->hide_row_nums == 0) {
       // Check if we already have Row #
       struct zsv_cell c = zsv_get_cell(parser, 0);
       if (c.len == ZSVSHEET_ROWNUM_HEADER_LEN && !memcmp(c.str, ZSVSHEET_ROWNUM_HEADER, c.len)) {
         zsvsheet_opts->hide_row_nums = 1;
         if (uibuff)
-          uibuff->has_row_num = 1;
+          uibuff->no_add_row_num = 1;
       }
     }
+    size_t rownum_column_offset = !zsvsheet_opts->hide_row_nums;
 
     original_row_num++;
     if (remaining_header_to_skip > 0) {
@@ -155,7 +156,7 @@ static int read_data(struct zsvsheet_ui_buffer **uibufferp,   // a new zsvsheet_
       continue;
     }
     if (uibuff) {
-      if (col_count + !buffer->opts.no_rownum_column > buffer->cols) {
+      if (col_count > buffer->cols) {
         if (zsvsheet_screen_buffer_grow(buffer, col_count) != zsvsheet_priv_status_ok)
           return -1;
       }
@@ -187,7 +188,6 @@ static int read_data(struct zsvsheet_ui_buffer **uibufferp,   // a new zsvsheet_
           sprintf(buff, "########");
         zsvsheet_screen_buffer_write_cell(buffer, rows_read, 0, (unsigned char *)buff);
       }
-      rownum_column_offset = 1;
     }
 
     for (size_t i = start_col; i < col_count && i + rownum_column_offset < zsvsheet_screen_buffer_cols(buffer); i++) {
@@ -262,14 +262,16 @@ static void *get_data_index(void *gdi) {
 static size_t zsvsheet_find_next(struct zsvsheet_ui_buffer *uib, const char *needle,
                                  struct zsvsheet_opts *zsvsheet_opts, size_t header_span,
                                  struct zsv_prop_handler *custom_prop_handler) {
+  struct zsvsheet_ui_buffer_opts uibopts = {0};
   struct zsvsheet_rowcol *input_offset = &uib->input_offset;
   struct zsvsheet_rowcol *buff_offset = &uib->buff_offset;
   size_t cursor_row = uib->cursor_row;
   zsvsheet_opts->find = needle;
   zsvsheet_opts->found_rownum = 0;
+  uibopts.zsvsheet_opts = zsvsheet_opts;
   // TO DO: check if it exists in current row, later column (and change 'cursor_row - 1' below to 'cursor_row')
-  read_data(&uib, NULL, input_offset->row + buff_offset->row + header_span + cursor_row - 1, 0, header_span,
-            zsvsheet_opts, custom_prop_handler);
+  read_data(&uib, &uibopts, input_offset->row + buff_offset->row + header_span + cursor_row - 1, 0, header_span,
+            custom_prop_handler);
   zsvsheet_opts->find = NULL;
   return zsvsheet_opts->found_rownum;
 }
diff --git a/app/sheet/screen_buffer.c b/app/sheet/screen_buffer.c
index 6008ed35..812adfc8 100644
--- a/app/sheet/screen_buffer.c
+++ b/app/sheet/screen_buffer.c
@@ -82,8 +82,6 @@ zsvsheet_screen_buffer_t zsvsheet_screen_buffer_new(size_t cols, struct zsvsheet
   if (opts->cell_buff_len < sizeof(void *) * 2)
     *stat = zsvsheet_priv_status_error;
   else {
-    if (!opts->no_rownum_column)
-      cols++;
     void *data = calloc(opts->rows, cols * opts->cell_buff_len);
     if (!data)
       *stat = zsvsheet_priv_status_memory;
@@ -110,9 +108,6 @@ enum zsvsheet_priv_status zsvsheet_screen_buffer_grow(zsvsheet_screen_buffer_t b
   size_t cell_buff_len = buff->opts.cell_buff_len;
   size_t old_row_len = old_cols * cell_buff_len;
 
-  if (!buff->opts.no_rownum_column)
-    cols++;
-
   size_t row_len = cols * cell_buff_len;
 
   assert(cols > old_cols);
diff --git a/app/sheet/screen_buffer.h b/app/sheet/screen_buffer.h
index cd1aa70a..a9012ed1 100644
--- a/app/sheet/screen_buffer.h
+++ b/app/sheet/screen_buffer.h
@@ -8,10 +8,9 @@
 typedef struct zsvsheet_screen_buffer *zsvsheet_screen_buffer_t;
 
 struct zsvsheet_screen_buffer_opts {
-  size_t cell_buff_len;  // default = 16. must be >= 2 * sizeof(void *)
-  size_t max_cell_len;   // length in bytes; defaults to 32767
-  size_t rows;           // rows to buffer. cannot be < 256
-  char no_rownum_column; // reserved. TO DO: if set, omit row num column
+  size_t cell_buff_len; // default = 16. must be >= 2 * sizeof(void *)
+  size_t max_cell_len;  // length in bytes; defaults to 32767
+  size_t rows;          // rows to buffer. cannot be < 256
 };
 
 zsvsheet_screen_buffer_t zsvsheet_screen_buffer_new(size_t cols, struct zsvsheet_screen_buffer_opts *opts,
diff --git a/app/sheet/transformation.c b/app/sheet/transformation.c
index 5d58f8ff..2b423b38 100644
--- a/app/sheet/transformation.c
+++ b/app/sheet/transformation.c
@@ -269,8 +269,10 @@ enum zsvsheet_status zsvsheet_push_transformation(zsvsheet_proc_context_t ctx,
     goto error;
   }
 
+  struct zsvsheet_opts zsvsheet_opts = {0};
   struct zsvsheet_ui_buffer_opts uibopts = {0};
 
+  uibopts.zsvsheet_opts = &zsvsheet_opts;
   uibopts.data_filename = zsvsheet_transformation_filename(trn);
   uibopts.write_after_open = 1;
 
diff --git a/app/sheet/ui_buffer.c b/app/sheet/ui_buffer.c
index 8a4f4c8c..b2bb770c 100644
--- a/app/sheet/ui_buffer.c
+++ b/app/sheet/ui_buffer.c
@@ -40,7 +40,7 @@ struct zsvsheet_ui_buffer {
   unsigned char index_ready : 1;
   unsigned char rownum_col_offset : 1;
   unsigned char index_started : 1;
-  unsigned char has_row_num : 1;
+  unsigned char no_add_row_num : 1;
   unsigned char mutex_inited : 1;
   unsigned char write_in_progress : 1;
   unsigned char write_done : 1;
@@ -92,11 +92,11 @@ void zsvsheet_ui_buffer_delete(struct zsvsheet_ui_buffer *ub) {
 }
 
 struct zsvsheet_ui_buffer_opts {
+  struct zsvsheet_opts *zsvsheet_opts;
   struct zsvsheet_screen_buffer_opts *buff_opts;
   const char *filename;
   const char *data_filename;
   struct zsv_opts zsv_opts; // options to use when opening this file
-  char no_rownum_col_offset;
   char write_after_open;
 };
 
@@ -108,9 +108,14 @@ struct zsvsheet_ui_buffer *zsvsheet_ui_buffer_new(zsvsheet_screen_buffer_t buffe
     uib->buffer = buffer;
     uib->mutex_inited = 1;
     memcpy(&uib->mutex, &init, sizeof(init));
-    if (!(uibopts && uibopts->no_rownum_col_offset))
-      uib->rownum_col_offset = 1;
+    uib->rownum_col_offset = !uibopts;
+
     if (uibopts) {
+      if (uibopts->zsvsheet_opts->hide_row_nums)
+        uib->no_add_row_num = 1;
+      else
+        uib->rownum_col_offset = 1;
+
       if (uibopts->filename && !(uib->filename = strdup(uibopts->filename))) {
         zsvsheet_ui_buffer_delete(uib);
         return NULL;
@@ -192,3 +197,9 @@ int zsvsheet_ui_buffer_pop(struct zsvsheet_ui_buffer **base, struct zsvsheet_ui_
   }
   return 0;
 }
+
+static const char *zsvsheet_ui_buffer_get_header(struct zsvsheet_ui_buffer *uib, size_t col) {
+  struct zsvsheet_screen_buffer *sb = uib->buffer;
+
+  return (char *)zsvsheet_screen_buffer_cell_display(sb, 0, col);
+}
diff --git a/app/sql.c b/app/sql.c
index 816758bd..02ced918 100644
--- a/app/sql.c
+++ b/app/sql.c
@@ -19,6 +19,8 @@
 #include <zsv/utils/writer.h>
 #include <zsv/utils/file.h>
 #include <zsv/utils/string.h>
+#include <zsv/utils/sql.h>
+#include "sql_internal.h"
 
 #include <unistd.h> // unlink
 
@@ -109,8 +111,6 @@ static char is_select_sql(const char *s) {
                                                         (const unsigned char *)s, strlen("select "));
 }
 
-#include "sql_internal.c"
-
 int ZSV_MAIN_FUNC(ZSV_COMMAND)(int argc, const char *argv[], struct zsv_opts *opts,
                                struct zsv_prop_handler *custom_prop_handler) {
   /**
diff --git a/app/test/Makefile b/app/test/Makefile
index cf56d255..99ea1d2d 100644
--- a/app/test/Makefile
+++ b/app/test/Makefile
@@ -618,7 +618,7 @@ test-sheet-cleanup:
 	@rm -f tmux-*.log
 	@tmux kill-server || printf ''
 
-test-sheet-all: test-sheet-1 test-sheet-2 test-sheet-3 test-sheet-4 test-sheet-5 test-sheet-6 test-sheet-7 test-sheet-8 test-sheet-9 test-sheet-10 test-sheet-11 test-sheet-12 test-sheet-13 test-sheet-14 test-sheet-subcommand test-sheet-prop-cmd-opt
+test-sheet-all: test-sheet-1 test-sheet-2 test-sheet-3 test-sheet-4 test-sheet-5 test-sheet-6 test-sheet-7 test-sheet-8 test-sheet-9 test-sheet-10 test-sheet-11 test-sheet-12 test-sheet-13 test-sheet-14 test-sheet-subcommand test-sheet-prop-cmd-opt test-sheet-pivot
 	@(for SESSION in $^; do ! tmux kill-session -t "$$SESSION" 2>/dev/null; done && ${TEST_PASS} || ${TEST_FAIL})
 
 TMUX_TERM=xterm-256color
@@ -807,6 +807,43 @@ test-sheet-prop-cmd-opt: ${BUILD_DIR}/bin/zsv_sheet${EXE} ${BUILD_DIR}/bin/zsv_p
 #	@tmux send-keys -t $@ "q"
 #	@${CMP} ${TMP_DIR}/$@.out expected/$@.out && ${TEST_PASS} || (echo 'Incorrect output:' && cat ${TMP_DIR}/$@.out && ${TEST_FAIL})
 
+test-sheet-pivot: test-sheet-pivot-1 test-sheet-pivot-2 test-sheet-pivot-3
+
+test-sheet-pivot-1: ${BUILD_DIR}/bin/zsv_sheet${EXE}
+	@${TEST_INIT}
+	@echo 'set-option default-terminal "${TMUX_TERM}"' > ~/.tmux.conf
+	@(tmux new-session -x 80 -y 25 -d -s "$@" "${PREFIX} $< worldcitiespop_mil.csv" && \
+	${EXPECT} $@ indexed && \
+	tmux send-keys -t $@ l v && \
+	${EXPECT} $@ groups && \
+	tmux send-keys -t $@ j j Enter && \
+	${EXPECT} $@ drilldown && \
+	tmux send-keys -t $@ G && \
+	${EXPECT} $@ && ${TEST_PASS} || ${TEST_FAIL})
+
+test-sheet-pivot-2: ${BUILD_DIR}/bin/zsv_sheet${EXE}
+	@${TEST_INIT}
+	@echo 'set-option default-terminal "${TMUX_TERM}"' > ~/.tmux.conf
+	@(tmux new-session -x 80 -y 25 -d -s "$@" "${PREFIX} $< -d 3 ../../data/test/mixed-line-endings.csv" && \
+	${EXPECT} $@ indexed && \
+	tmux send-keys -t $@ l l l v && \
+	${EXPECT} $@ groups && \
+	tmux send-keys -t $@ j j Enter && \
+	${EXPECT} $@ && ${TEST_PASS} || ${TEST_FAIL})
+
+test-sheet-pivot-3: ${BUILD_DIR}/bin/zsv_sheet${EXE}
+	@${TEST_INIT}
+	@echo 'set-option default-terminal "${TMUX_TERM}"' > ~/.tmux.conf
+	@(tmux new-session -x 80 -y 25 -d -s "$@" "${PREFIX} $< worldcitiespop_mil.csv" && \
+	${EXPECT} $@ indexed && \
+	tmux send-keys -t $@ V && \
+	${EXPECT} $@ prompt && \
+	tmux send-keys -l -t $@ "iif(coalesce(Population, '') = '', 'Unknown', 'Populated')" && \
+	tmux send-keys -t $@ Enter && \
+	${EXPECT} $@ groups && \
+	tmux send-keys -t $@ Enter && \
+	${EXPECT} $@ && ${TEST_PASS} || ${TEST_FAIL})
+
 benchmark-sheet-index: ${BUILD_DIR}/bin/zsv_sheet${EXE} ${TIMINGS_CSV}
 	@${TEST_INIT}
 	@if [ "${BIG_FILE}" = "none" ]; then \
diff --git a/app/test/expected/test-sheet-pivot-1-drilldown.out b/app/test/expected/test-sheet-pivot-1-drilldown.out
new file mode 100644
index 00000000..bd14fadf
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-1-drilldown.out
@@ -0,0 +1,25 @@
+Row #     Country   City      AccentCit Region    Populatio Latitude  Longitude
+546       af        abakeh    Abakeh    24                  36.67363  69.078194
+549       af        abakheyl' Abakheyl' 35                  34.744167 70.287778
+551       af        aband     Aband     42                  35.474953 69.871144
+556       af        abasali   Abasali   39                  32.813402 65.968042
+558       af        abaskhank Abaskhank 29                  32.503976 69.209795
+560       af        abas khel Abas Khel 28                  31.975853 67.59182
+561       af        abaskheyl Abaskheyl 28                  31.975853 67.59182
+563       af        `abaskust `Abaskust 27                  34.331309 67.640744
+576       af        ab barik  Ab Barik  09                  34.651024 66.254311
+577       af        `abbas    `Abbas    08                  33.333    67.643278
+582       af        `abbaskha `Abbaskha 29                  32.469231 69.20712
+583       af        `abbas kh `Abbas Kh 29                  32.469231 69.20712
+588       af        `abbas kh `Abbas Kh 29                  32.671879 69.134674
+589       af        `abbaskhe `Abbaskhe 29                  32.671879 69.134674
+590       af        abbaskhel Abbaskhel 29                  32.831993 69.12336
+593       af        `abbaskhe `Abbaskhe 29                  32.831389 69.260556
+594       af        abbaskhey Abbaskhey 29                  32.671879 69.134674
+596       af        `abbaskhe `Abbaskhe 29                  32.831993 69.12336
+600       af        `abbas ku `Abbas Ku 27                  34.331309 67.640744
+604       af        abbazha-y Abbazha-y 10                  31.791857 64.566416
+607       af        ab bazha- Ab Bazha- 10                  31.719049 64.600709
+608       af        abbazha-y Abbazha-y 10                  31.719049 64.600709
+611       af        abbedak   Abbedak   09                  33.482286 64.310608
+? for help 546
diff --git a/app/test/expected/test-sheet-pivot-1-groups.out b/app/test/expected/test-sheet-pivot-1-groups.out
new file mode 100644
index 00000000..05b370a3
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-1-groups.out
@@ -0,0 +1,25 @@
+value                                   Count
+ad                                      27
+ae                                      147
+af                                      27822
+ag                                      55
+ai                                      14
+al                                      4730
+am                                      896
+an                                      75
+ao                                      6170
+ar                                      2817
+at                                      4740
+au                                      3403
+aw                                      37
+az                                      3522
+ba                                      5076
+bb                                      165
+bd                                      8280
+be                                      5056
+bf                                      3248
+bg                                      6258
+bh                                      102
+bi                                      646
+bj                                      1331
+? for help ad
diff --git a/app/test/expected/test-sheet-pivot-1-indexed.out b/app/test/expected/test-sheet-pivot-1-indexed.out
new file mode 100644
index 00000000..610fb180
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-1-indexed.out
@@ -0,0 +1,25 @@
+Row #     Country   City      AccentCit Region    Populatio Latitude  Longitude
+1         ir        sarmaj-e  Sarmaj-e  13                  34.3578   47.5207
+2         ad        aixirival Aixirival 06                  42.466666 1.5
+3         mm        mokho-atw Mokho-atw 09                  18.033333 96.75
+4         id        selingon  Selingon  17                  -8.8374   116.4914
+5         ir        berimvand Berimvand 13                  34.2953   47.1096
+6         pl        chomiaza  Chomiaza  73                  52.7508   17.841793
+7         mg        itona     Itona     02                  -23.86666 47.216666
+8         ad        andorra-v Andorra-V 07                  42.5      1.5166667
+9         mx        la tortug La Tortug 25                  25.75     -108.3333
+10        us        asaph     Asaph     PA                  41.770833 -77.40527
+11        ad        andorre-v Andorre-V 07                  42.5      1.5166667
+12        ru        dolmatova Dolmatova 71                  57.436791 63.279522
+13        ro        escu      Escu      13                  47.133333 23.533333
+14        us        la presa  La Presa  CA        35119     32.708055 -116.9963
+15        pk        makam khu Makam Khu 04                  33.650863 72.551536
+16        ad        aubinya   Aubinyà   06                  42.45     1.5
+17        mm        kiosong   Kiosöng   11                  22.583333 97.05
+18        tr        donencay  Dönençay  28                  40.266667 38.583333
+19        it        roncaglia Roncaglia 05                  45.05     9.8
+20        ml        kourmouss Kourmouss 04                  14.75     -5.033333
+21        id        lamogo    Lamogo    38                  -4.3945   119.9028
+22        ad        casas vil Casas Vil 03                  42.533333 1.5666667
+23        ru        otdeleniy Otdeleniy 86                  51.726473 39.714345
+? for help 1
diff --git a/app/test/expected/test-sheet-pivot-1.out b/app/test/expected/test-sheet-pivot-1.out
new file mode 100644
index 00000000..d2f20474
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-1.out
@@ -0,0 +1,25 @@
+Row #     Country   City      AccentCit Region    Populatio Latitude  Longitude
+89222     af        zungur ka Zungur Ka 27                  33.993056 68.658056
+89223     af        zunun     Zunun     01                  38.438492 70.904387
+89224     af        zu ol faq Zu ol Faq 03                  35.616782 68.670307
+89225     af        zu ol faq Zu ol Faq 27                  34.1575   68.501389
+89232     af        zur baraw Zur Baraw 34                  35.028791 71.507898
+89235     af        zuri      Zuri      11                  33.94062  62.160912
+89238     af        zur kalay Zur Kalay 35                  34.670345 70.165192
+89244     af        zur kowt  Zur Kowt  37                  33.542222 69.734167
+89246     af        zurmatiya Zurmatiya 28                  32.138117 66.835273
+89248     af        zurmat    Zurmat    36                  33.437782 69.02774
+89249     af        zurni     Zurni     09                  33.568987 63.289317
+89252     af        zurwam    Zurwam    23                  31.439167 66.936667
+89256     af        zutni khe Zutni Khe 36                  33.360477 68.973862
+89258     af        zutni khe Zutni Khe 36                  33.360477 68.973862
+89261     af        zu        Zu        01                  36.84154  71.069323
+89262     af        zvaka     Zvaka     29                  32.968334 68.809853
+89264     af        zwaka     Zwaka     29                  32.968334 68.809853
+89267     af        zyan say  Zyan Say  07                  35.864952 64.278152
+89279     af        zyaratjay Zyaratjay 11                  34.197386 62.140143
+89281     af        zyarat ka Zyarat Ka 18                  34.288611 71.138889
+89282     af        zyarat ka Zyarat Ka 23                  31.355826 66.535299
+89283     af        zyarat ka Zyarat Ka 35                  34.738611 70.269444
+89286     af        zyarat    Zyarat    39                  32.523283 65.905489
+? for help 89286
diff --git a/app/test/expected/test-sheet-pivot-2-groups.out b/app/test/expected/test-sheet-pivot-2-groups.out
new file mode 100644
index 00000000..d933c39e
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-2-groups.out
@@ -0,0 +1,25 @@
+value                                   Count
+ C1                                     1
+ C10                                    1
+ C100                                   1
+ C1000                                  1
+ C1001                                  1
+ C1002                                  1
+ C1003                                  1
+ C1004                                  1
+ C1005                                  1
+ C1006                                  1
+ C1007                                  1
+ C1008                                  1
+ C1009                                  1
+ C101                                   1
+ C1010                                  1
+ C1011                                  1
+ C1012                                  1
+ C1013                                  1
+ C1014                                  1
+ C1015                                  1
+ C1016                                  1
+ C1017                                  1
+ C1018                                  1
+? for help  C1
diff --git a/app/test/expected/test-sheet-pivot-2-indexed.out b/app/test/expected/test-sheet-pivot-2-indexed.out
new file mode 100644
index 00000000..b7f86738
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-2-indexed.out
@@ -0,0 +1,25 @@
+Row #               HA1 HA2 HA3          HB1  HB2  HB3       HC1  HC2  HC3
+1                   A1                   B1                  C1
+2                   A2                   B2                  C2
+3                   A3                   B3                  C3
+4                   A4                   B4                  C4
+5                   A5                   B5                  C5
+6                   A6                   B6                  C6
+7                   A7                   B7                  C7
+8                   A8                   B8                  C8
+9                   A9                   B9                  C9
+10                  A10                  B10                 C10
+11                  A11                  B11                 C11
+12                  A12                  B12                 C12
+13                  A13                  B13                 C13
+14                  A14                  B14                 C14
+15                  A15                  B15                 C15
+16                  A16                  B16                 C16
+17                  A17                  B17                 C17
+18                  A18                  B18                 C18
+19                  A19                  B19                 C19
+20                  A20                  B20                 C20
+21                  A21                  B21                 C21
+22                  A22                  B22                 C22
+23                  A23                  B23                 C23
+? for help 1
diff --git a/app/test/expected/test-sheet-pivot-2.out b/app/test/expected/test-sheet-pivot-2.out
new file mode 100644
index 00000000..17285ddd
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-2.out
@@ -0,0 +1,25 @@
+Row #               HA1 HA2 HA3         HB1  HB2  HB3       HC1  HC2  HC3
+100                 A100                 B100                C100
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+? for help 100
diff --git a/app/test/expected/test-sheet-pivot-3-groups.out b/app/test/expected/test-sheet-pivot-3-groups.out
new file mode 100644
index 00000000..98a9d692
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-3-groups.out
@@ -0,0 +1,25 @@
+value                                   Count
+Populated                               15166
+Unknown                                 984834
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+? for help Populated
diff --git a/app/test/expected/test-sheet-pivot-3-indexed.out b/app/test/expected/test-sheet-pivot-3-indexed.out
new file mode 100644
index 00000000..610fb180
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-3-indexed.out
@@ -0,0 +1,25 @@
+Row #     Country   City      AccentCit Region    Populatio Latitude  Longitude
+1         ir        sarmaj-e  Sarmaj-e  13                  34.3578   47.5207
+2         ad        aixirival Aixirival 06                  42.466666 1.5
+3         mm        mokho-atw Mokho-atw 09                  18.033333 96.75
+4         id        selingon  Selingon  17                  -8.8374   116.4914
+5         ir        berimvand Berimvand 13                  34.2953   47.1096
+6         pl        chomiaza  Chomiaza  73                  52.7508   17.841793
+7         mg        itona     Itona     02                  -23.86666 47.216666
+8         ad        andorra-v Andorra-V 07                  42.5      1.5166667
+9         mx        la tortug La Tortug 25                  25.75     -108.3333
+10        us        asaph     Asaph     PA                  41.770833 -77.40527
+11        ad        andorre-v Andorre-V 07                  42.5      1.5166667
+12        ru        dolmatova Dolmatova 71                  57.436791 63.279522
+13        ro        escu      Escu      13                  47.133333 23.533333
+14        us        la presa  La Presa  CA        35119     32.708055 -116.9963
+15        pk        makam khu Makam Khu 04                  33.650863 72.551536
+16        ad        aubinya   Aubinyà   06                  42.45     1.5
+17        mm        kiosong   Kiosöng   11                  22.583333 97.05
+18        tr        donencay  Dönençay  28                  40.266667 38.583333
+19        it        roncaglia Roncaglia 05                  45.05     9.8
+20        ml        kourmouss Kourmouss 04                  14.75     -5.033333
+21        id        lamogo    Lamogo    38                  -4.3945   119.9028
+22        ad        casas vil Casas Vil 03                  42.533333 1.5666667
+23        ru        otdeleniy Otdeleniy 86                  51.726473 39.714345
+? for help 1
diff --git a/app/test/expected/test-sheet-pivot-3-prompt.out b/app/test/expected/test-sheet-pivot-3-prompt.out
new file mode 100644
index 00000000..edaa6c71
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-3-prompt.out
@@ -0,0 +1,25 @@
+Row #     Country   City      AccentCit Region    Populatio Latitude  Longitude
+1         ir        sarmaj-e  Sarmaj-e  13                  34.3578   47.5207
+2         ad        aixirival Aixirival 06                  42.466666 1.5
+3         mm        mokho-atw Mokho-atw 09                  18.033333 96.75
+4         id        selingon  Selingon  17                  -8.8374   116.4914
+5         ir        berimvand Berimvand 13                  34.2953   47.1096
+6         pl        chomiaza  Chomiaza  73                  52.7508   17.841793
+7         mg        itona     Itona     02                  -23.86666 47.216666
+8         ad        andorra-v Andorra-V 07                  42.5      1.5166667
+9         mx        la tortug La Tortug 25                  25.75     -108.3333
+10        us        asaph     Asaph     PA                  41.770833 -77.40527
+11        ad        andorre-v Andorre-V 07                  42.5      1.5166667
+12        ru        dolmatova Dolmatova 71                  57.436791 63.279522
+13        ro        escu      Escu      13                  47.133333 23.533333
+14        us        la presa  La Presa  CA        35119     32.708055 -116.9963
+15        pk        makam khu Makam Khu 04                  33.650863 72.551536
+16        ad        aubinya   Aubinyà   06                  42.45     1.5
+17        mm        kiosong   Kiosöng   11                  22.583333 97.05
+18        tr        donencay  Dönençay  28                  40.266667 38.583333
+19        it        roncaglia Roncaglia 05                  45.05     9.8
+20        ml        kourmouss Kourmouss 04                  14.75     -5.033333
+21        id        lamogo    Lamogo    38                  -4.3945   119.9028
+22        ad        casas vil Casas Vil 03                  42.533333 1.5666667
+23        ru        otdeleniy Otdeleniy 86                  51.726473 39.714345
+Pivot table: Enter group-by SQL expr:
diff --git a/app/test/expected/test-sheet-pivot-3.out b/app/test/expected/test-sheet-pivot-3.out
new file mode 100644
index 00000000..d4f0d5f8
--- /dev/null
+++ b/app/test/expected/test-sheet-pivot-3.out
@@ -0,0 +1,25 @@
+Row #     Country   City      AccentCit Region    Populatio Latitude  Longitude
+14        us        la presa  La Presa  CA        35119     32.708055 -116.9963
+54        ad        les escal Les Escal 08        15854     42.5      1.5333333
+72        us        lawrence  Lawrence  MA        72609     42.706944 -71.16361
+94        ae        abu dhabi Abu Dhabi 01        603687    24.466667 54.366667
+208       ph        general l General L H3        3132      10.833333 123.56666
+225       gr        mitikas   Mítikas   31        934       38.666666 20.933333
+307       ru        shudayag  Shudayag  34        3446      63.526652 53.605822
+385       ru        shcheglov Shcheglov 42        3095      60.001399 30.783441
+573       sk        prievidza Prievidza 01        52987     48.766666 18.633333
+640       jp        matsubara Matsubara 32        130857    34.566667 135.55
+660       gr        velventos Velventó  11        3378      40.251666 22.063055
+679       pt        arazede   Arazede   07        5906      40.286268 -8.649989
+716       ru        porkhov   Porkhov   60        11886     57.765016 29.556121
+751       us        winter sp Winter Sp FL        32658     28.698611 -81.30833
+824       ru        kubinka   Kubinka   47        25942     55.579569 36.703919
+830       no        alsvag    Alsvåg    09        335       68.9      15.283333
+913       pl        jozefow   Jozefow   78        17910     51.806452 21.220953
+914       us        del rio   Del Rio   TX        36068     29.362500 -100.8963
+1190      ru        kamenka   Kamenka   06        3258      65.887591 44.112612
+1330      lt        venta     Venta     40        3270      56.2      22.7
+1432      ro        farcasu   Farcasu   26        3620      44.6      23.75
+1532      sl        largo     Largo     03        4484      8.2666667 -12.15
+1562      pk        eminabad  Eminabad  04        22677     32.042188 74.259435
+? for help 14
diff --git a/include/zsv/ext.h b/include/zsv/ext.h
index 392399a2..44ca3a91 100644
--- a/include/zsv/ext.h
+++ b/include/zsv/ext.h
@@ -238,6 +238,11 @@ struct zsv_ext_callbacks {
    */
   zsvsheet_status (*ext_sheet_open_file)(zsvsheet_proc_context_t, const char *filepath, struct zsv_opts *zopts);
 
+  /**
+   * Open a tabular file with more available options
+   */
+  zsvsheet_status (*ext_sheet_open_file_opts)(struct zsvsheet_proc_context *ctx, struct zsvsheet_open_file_opts *opts);
+
   /**
    * Set custom context
    * @param on_close optional callback to invoke when the buffer is closed
diff --git a/include/zsv/ext/sheet.h b/include/zsv/ext/sheet.h
index f3e6b7e6..51c1e1c0 100644
--- a/include/zsv/ext/sheet.h
+++ b/include/zsv/ext/sheet.h
@@ -1,6 +1,8 @@
 #ifndef ZSVSHEET_H
 #define ZSVSHEET_H
 
+#include <zsv.h>
+
 /* custom sheet handler id */
 typedef int zsvsheet_proc_id_t;
 
@@ -22,6 +24,13 @@ typedef struct zsvsheet_subcommand_context *zsvsheet_subcommand_context_t;
 typedef void *zsvsheet_buffer_t;
 // int zsvsheet_ext_keypress(zsvsheet_proc_context_t);
 
+struct zsvsheet_open_file_opts {
+  const char *filename;
+  const char *data_filename;
+  struct zsv_opts *zsv_opts;
+  char no_auto_row_num;
+};
+
 typedef struct zsvsheet_transformation *zsvsheet_transformation;
 /**
  * Transformation options passed to zsvsheet_push_transformation