sql: add assignment cast for UPDATEs #74180

mgartner · 2021-12-21T23:51:53Z

opt: fix FK WithScan column type

Previously, the WithScan columns of cascade FK updates were given the
type of the child table's target column. This was incorrect when the
parent column type did not match. This commit fixes the issue by given
the WithScan columns the type of the buffered columns used to update the
parent relation.

This did not cause any known bugs, but it is required to implement
assignment casts with FK cascades.

Release note: None

sql: add assignment cast for UPDATEs

Fixes #70628

Release note: None

opt: give synthesized assignment cast columns descriptive names

Columns synthesized for assignment casts now have more descriptive
metadata names in the form <target_column_name>_cast. This is purely
an aesthetic change and has no effect on semantics.

Release note: None

cockroach-teamcity · 2021-12-21T23:52:02Z

This change is

rytaft

Reviewed 2 of 2 files at r1, 22 of 22 files at r2, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @cucaroach, @mgartner, and @RaduBerinde)

pkg/sql/opt/optbuilder/scope.go, line 320 at r2 (raw file):

}

// getColumn returns the scopeColumn with the given id and reference name

getColumn -> getColumnWithIDAndreferenceName

pkg/sql/logictest/testdata/logic_test/cast, line 384 at r2 (raw file):

EXECUTE update_c('foo'::STRING)

statement

should this be statement ok?

pkg/sql/logictest/testdata/logic_test/cast, line 392 at r2 (raw file):

""

statement

ditto

pkg/sql/logictest/testdata/logic_test/cast, line 409 at r2 (raw file):


statement error \"char\" out of range
UPDATE assn_cast SET qc = 1234

why does this one fail while the previous one succeeds? (maybe add a comment)

pkg/sql/opt/optbuilder/testdata/partial-indexes, line 542 at r2 (raw file):

# Regression test for #61520. The new value for column a should be in-scope when
# building the partial index PUT expression when the value in the FROM clause
# must assignment cast.

nit: must assignment cast -> must be assignment cast ?

pkg/sql/opt/xform/testdata/external/trading-mutation, line 1595 at r2 (raw file):

      │              └── q:37
      └── projections
           ├── assignment-cast: DECIMAL(10,4) [as=column53:53, outer=(23,25), immutable]

can we give the new column a friendly name? (e.g., just keep the name buyprice here)

Previously, the WithScan columns of cascade FK updates were given the type of the child table's target column. This was incorrect when the parent column type did not match. This commit fixes the issue by given the WithScan columns the type of the buffered columns used to update the parent relation. This did not cause any known bugs, but it is required to implement assignment casts with FK cascades. Release note: None

Fixes cockroachdb#70628 Release note: None

Columns synthesized for assignment casts now have more descriptive metadata names in the form `<target_column_name>_cast`. This is purely an aesthetic change and has no effect on semantics. Release note: None

mgartner

Reviewable status: complete! 0 of 0 LGTMs obtained (and 1 stale) (waiting on @cucaroach, @RaduBerinde, and @rytaft)

pkg/sql/opt/optbuilder/scope.go, line 320 at r2 (raw file):