fix(optimizer)!: annotate type for databricks REGR_AVGY, REGR_COUNT, REGR_INTERCEPT, REGR_R2, REGR_SLOPE

[fivetran-amrutabhimsenayachit]

Summary

Adds Databricks type inference support for REGR_AVGY (DOUBLE), REGR_COUNT (BIGINT), REGR_INTERCEPT (DOUBLE), REGR_R2 (DOUBLE), and REGR_SLOPE (DOUBLE), plus fixture coverage for all five functions.

Issue: REGR_FUNC(DISTINCT col1, col2) raised a parse error in Databricks because the base parser's DISTINCT handler consumed all comma-separated arguments into a single node, leaving the second required argument missing.

Fix: Added a custom parser method in DatabricksParser that reads only the first argument under DISTINCT, then parses the rest normally.

Tickets

• RD-1229638 (REGR_AVGY) — DOUBLE
• RD-1229639 (REGR_COUNT) — BIGINT
• RD-1229640 (REGR_INTERCEPT) — DOUBLE
• RD-1229641 (REGR_R2) — DOUBLE
• RD-1229642 (REGR_SLOPE) — DOUBLE

Test plan

python3 -c "import sqlglot; print(repr(sqlglot.parse_one('SELECT REGR_AVGY(DISTINCT tbl.double_col, tbl.double_col) FROM tbl', dialect='databricks').expressions[0]))"


RegrAvgy(
  this=Distinct(
    expressions=[
      Column(
        this=Identifier(this=double_col, quoted=False),
        table=Identifier(this=tbl, quoted=False))]),
  expression=Column(
    this=Identifier(this=double_col, quoted=False),
    table=Identifier(this=tbl, quoted=False))

• make style — PASS
• make unit — PASS

[github-actions]

SQLGlot Integration Test Results

✅ All tests passed

Comparing:

• this branch (sqlglot:type-inference-batch-3 @ sqlglot b8a2c8a)
• baseline (main @ sqlglot aedf83a)

Overall

main: 192416 total, 153530 passed (pass rate: 79.8%)

sqlglot:type-inference-batch-3: 180222 total, 142385 passed (pass rate: 79.0%)

Transitions:
No change

Dialect pair changes: 0 previous results not found, 3 current results not found

✅ All tests passed

[geooo109]

Left a comment, also we should add roundtrip tests for ALL/DISTINCT if they are missing.

[geooo109]

Did you verify where the DISTINCT is applied on for each function of the REGR list ? (on 1-arg or on both args)

For example in REGR_AVGX , REGR_AVGY as it seems the distinct is applied on 1-arg (x and y respectively). On the other hand, forREGR_COUNT distinct is applied on both args (as a tuple). So, the parsing function should seperate the args based on this ^ and not seperate it for all the functions in the REGR_ list.

So, let's verify each function and parse accordingly.

[geooo109]

Looks pretty similar to _parse_quantile_function of hive right ?