Support column_list in CONTAINS

[jaspal007]

Description

Specifies two or more columns, separated by commas. column_list must be enclosed in parentheses. Unless language_term is specified, the language of all columns of column_list must be the same.

Issues

Previously in Babelfish the support for multiple columns was unsupported for simple terms in contains clause and it gave syntax error.

• This was the error thrown while using multiple column syntax at the TDS endpoint of Babelfish

Changes made to fix the issue

To resolve this issue we created a new grammar var_name_list and opt_var_name_list to support the list of columns passed in the TSQL query.
We also modified the grammar for single column to pass it as a list opt_var_name to bring singularity in the way both the column name and column list are being passed into the backend parser.

• Now the TDS endpoint supports multiple column syntax.

Task: BABEL-4239
Authored-by: Jaspal Singh [email protected]
Signed-off-by: Jaspal Singh [email protected]

Issues Resolved

BABEL-4239
Extension side PR link: Support column_list in CONTAINS #3438

Check List

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[jaspal007]

The changes in engine are not required, any change in the grammar needed is to be done in gram-tsql-rule.y file on extension side.