Local Examples: Add --binary-as-hex=false flag to mysql alias

[mattlord]

Description

The Vitess local examples (source) are a common first touch experience for users. They are regularly confused or curious as to why many of the columns in the examples show up as HEX in the query results. The reason for this is that we use VARBINARY types throughout — in some rare cases like keyspace_id it makes sense, but most like customer.email are pure text. This makes understanding what's happening and quickly confirming at-a-glance results as expected more difficult and poses a minor hurdle when it's already quite a lot to get started with Vitess.

In this PR, we add the --binary-as-hex=false mysql client flag to the mysql alias we setup to both increase awareness of that flag and so that more people are using it by default (source ../common/env.sh).

The bigger effort would be to move most of our VARBINARY usage under ./examples to VARCHAR. This offers a more intuitive/expected experience while also more closely matching what users will be using for similar types of data. I can only guess that VARBINARY was used initially (many years ago now) because at the time Vitess did not have MySQL collation support. Vitess now has MySQL compatible collations so I think it's worth doing this work. For that I've created an issue and marked it as a good first issue for anyone that's interested in a relatively simple and straightforward first contribution to Vitess.

Related Issue(s)

• Feature Request: Move most VARBINARY columns to VARCHAR in examples #15997

Checklist

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• Documentation was added or is not required

[vitess-bot]

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