`TEXT` type for MySQL dialect

exasol / virtual-schemas

Entry point repository for the EXASOL Virtual Schemas

http://www.exasol.com

MIT License

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`TEXT` type for MySQL dialect #320

Closed redcatbear closed 4 years ago

redcatbear commented 4 years ago

Situation

MySQL knows the type TEXT which can hold large amounts of text. Exasol's closest match is VARCHAR. At least documents up to 2 million characters should be usable through the MySQL dialect for Exasol Virtual Schema.

Acceptance Criteria

UTF text from MySQL TEXT columns visible as VARCHAR in VS (up to maximum Exasol VARCHAR size).

redcatbear commented 4 years ago

Looking at the code the BaseColumnMetadataReader already handles LONGVARCHAR correctly. And that is what the MySQL JDBC driver maps TEXT fields to.

See:

https://dev.mysql.com/doc/connector-j/8.0/en/connector-j-reference-type-conversions.html
https://dev.mysql.com/doc/refman/8.0/en/storage-requirements.html