WIP: Support constraints for ALTER COLUMN TYPE #48516
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Enable experimental ALTER COLUMN TYPE general using SET enable_experimental_alter_column_type_general = true; Release note (sql change): Support for ALTER COLUMN TYPE online schema change for changing a column type's data.
Enable experimental ALTER COLUMN TYPE general using SET enable_experimental_alter_column_type_general = true; Release note (sql change): Support for ALTER COLUMN TYPE online schema change for changing a column type's data.
Rewrite constraints to support the new data type of the column. In a check constraint, any binary expression that contains the column will have the opposite side casted to the type of the column. Example: Given column x INT with check constraint (x > 5) if x is changed to a FLOAT, the new constraint will be (x > 5::FLOAT).
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Depends on #46933
Fixes #48288
Support altering data type of a column that has check constraints. Rewrite constraints to support the new data type of the column.In a check constraint, any binary expression that contains the column will have the opposite side casted to the type of the column.
Example: Given column x INT with check constraint (x > 5) if x is changed to a FLOAT, the new constraint will be (x > 5::FLOAT).
Right now, the DFS naively checks if a BinaryExpr/ComparisonExpr is contains the column and casts the opposite side to the cast. Furthermore if either the Left or Right Expr of a BinaryExpr/Comparison was changed, the opposite side is casted as well.