Not-So-BigQuery

An emulator for Google BigQuery, that can be run locally, backed by PostgreSQL.

Compatibility

API Endpoints

More info here.

Functions

More info here.

SQL Compatibility

Since BigQuery uses its own SQL implementation, there can be and there are functionalities that will not work. To achieve most of the features that BigQuery provides, Not-So-BigQuery uses its own query parser to translate to a PostgreSQL-compatible query.

Supported BigQuery syntax

Link to the full query statement syntax: https://cloud.google.com/bigquery/docs/reference/standard-sql/query-syntax

query_statement:
    query_expr

query_expr:
    [ WITH with_query_name AS ( query_expr ) [, ...] ]
    select | ( query_expr )
    [ ORDER BY expression [{ ASC | DESC }] [, ...] ]
    [ LIMIT count [ OFFSET skip_rows ] ]

select:
    SELECT [{ ALL | DISTINCT }]
        { [ expression. ]*
        | expression [ [ AS ] alias ] } [, ...]
    [ FROM from_item  [, ...] ]
    [ WHERE expression ]
    [ GROUP BY expression [, ...] ]
    [ HAVING expression ]

from_item: {
    table_name [ [ AS ] alias ]
    join |
    ( query_expr ) [ [ AS ] alias ] |
    with_query_name [ [ AS ] alias ]
}

join:
   from_item [ join_type ] JOIN from_item
   [ ON expression | USING ( join_column [, ...] ) ]

join_type:
   { INNER | CROSS | FULL [OUTER] | LEFT [OUTER] | RIGHT [OUTER] }

Where the expression is the following:

expression:
    literal_value |
    [ [ [ [ project_name . ] dataset_name . ] table_name . ] column_name ] |
    unary_operator expression |
    expression binary_operator expression |
    function_name ( [ expression [, ...] | * ] ) |
    ( expression [, ...] ) |
    CAST ( expression AS type_name ) |
    EXTRACT ( part FROM date_expression ) |
    expression IS [ NOT ] NULL | 
    expression IS [ NOT ] expression |
    expression [ NOT ] IN ( { expression | select } )

literal_value:
    numeric_literal |
    string_literal |
    NULL | TRUE | FALSE

unary_operator:
    NOT

binary_operator:
    AND | OR |
    < | <= | > | >= | = | <> | != 

Usage from source

To run the app

docker-compose up app

This will start Not-So-BigQuery in a container, and expose port 5443 on your host.

After this, you can configure your library to use http://localhost:5443/ as the API endpoint to reach BigQuery.

NodeJS

const bq = new BigQuery({ apiEndpoint: 'localhost:5443' });

Ruby

bigquery = Google::Cloud::Bigquery.new(endpoint: 'http://localhost:5443/')

To clear the storage

docker-compose rm -fs postgres && docker volume rm -f not-so-bigquery_db-data

Contributions

Contributions greatly appreciated.