fix(redshift): roundtrip support for CURRENT_USER_ID and USER

[fivetran-kwoodbeck]

SELECT USER and SELECT CURRENT_USER_ID were being quoted as "USER" and "CURRENT_USER_ID" because they were treated as reserved-word identifiers. Both are Redshift pseudo-columns that should parse and generate as bare keywords. Additionally, user used as a table name (e.g. FROM salesforce.user) was causing a ParseError.

-- before
SELECT USER            → SELECT "USER"
SELECT CURRENT_USER_ID → SELECT "CURRENT_USER_ID"
FROM salesforce.user   → ParseError

-- after
SELECT USER            → SELECT USER
SELECT CURRENT_USER_ID → SELECT CURRENT_USER_ID
FROM salesforce.user   → SELECT ... FROM salesforce."user"

[geooo109]

@fivetran-kwoodbeck USER is a synonym for CURRENT_USER in redshift USER docs. As a result, we can map the USER to CURRENT_USER here to simplify things. (we have already support for CURRENT_USER). We do this for other dialects, check here. Let me know if this works.

[github-actions]

SQLGlot Integration Test Results

Comparing:

• this branch (sqlglot:fix/redshift-current_user_id, sqlglot version: fix/redshift-current_user_id)
• baseline (sqlglot:cold-prql-test, sqlglot version: cold-prql-test)

By Dialect

dialect	sqlglot:cold-prql-test	sqlglot:fix/redshift-current_user_id	transitions	links
databricks -> databricks	1370/1370 passed (100.0%)	1370/1370 passed (100.0%)	No change	full result / delta
postgres -> postgres	6042/6042 passed (100.0%)	6042/6042 passed (100.0%)	No change	full result / delta
redshift -> redshift	7100/7101 passed (100.0%)	7101/7101 passed (100.0%)	1 fail -> pass	full result / delta
snowflake -> snowflake	63027/63027 passed (100.0%)	63027/63027 passed (100.0%)	No change	full result / delta
bigquery -> bigquery	23497/23497 passed (100.0%)	23497/23497 passed (100.0%)	No change	full result / delta

Overall

sqlglot:cold-prql-test: 101037 total, 101036 passed (pass rate: 100.0%), sqlglot version: cold-prql-test

sqlglot:fix/redshift-current_user_id: 101037 total, 101037 passed (pass rate: 100.0%), sqlglot version: fix/redshift-current_user_id

Transitions:
1 fail -> pass

✅ 61 test(s) passed

[fivetran-kwoodbeck]

@fivetran-kwoodbeck USER is a synonym for CURRENT_USER in redshift USER docs. As a result, we can map the USER to CURRENT_USER here to simplify things. (we have already support for CURRENT_USER). We do this for other dialects, check here. Let me know if this works.

@geooo109 Sounds good, it's been updated