On Wed, Aug 21, 2024 at 4:57 PM Peter Eisentraut <pe...@eisentraut.org> wrote:
>
+ /*
+ * Cannot specify USING when altering type of a generated column, because
+ * that would violate the generation expression.
+ */
+ if (attTup->attgenerated && def->cooked_default)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
+ errmsg("cannot specify USING when altering type of generated column"),
+ errdetail("Column \"%s\" is a generated column.", colName)));
+
errcode should be ERRCODE_FEATURE_NOT_SUPPORTED?
also
CREATE TABLE gtest27 (
a int,
b text collate "C",
x text GENERATED ALWAYS AS ( b || '_2') STORED
);
ALTER TABLE gtest27 ALTER COLUMN x TYPE int;
ERROR: column "x" cannot be cast automatically to type integer
HINT: You might need to specify "USING x::integer".
should we do something for the errhint, since this specific errhint is wrong?
