(2010/02/02 9:48), KaiGai Kohei wrote: >>> Also, the ALTER COLUMN TYPE case should be also fixed in the 9.1 release >>> (or 9.0.1?). >> >> If the fix is something we could commit for 9.0.1, then we ought to do >> it now before 9.0 is released. If you want to submit a follow-on >> patch to address ALTER COLUMN TYPE once this is committed, then please >> do so. > > The attached patch also fixes ALTER COLUMN TYPE case. > > It replaced the 'recursing' argument in ATPrepCmd() by 'expected_parents', > and it is delivered to ATPrepAlterColumnType(). The logic to forbid altering > the column type is same as renameatt(). > ATSimpleRecursion() is also modified to use forboth() to call ATPrepCmd() > recursively. > > One concern is at ATOneLevelRecursion() which is called by ATPrepAddColumn() > only, and it also calls ATPrepCmd() for the direct children. > Right now, I set 1 on the 'expected_parents'. However, IMO, here is no reason > why we cannot rewrite the ATPrepAddColumn() using ATSimpleRecursion(). > > Eventually, ATExecAddColumn() shall be invoked several times for same column, > if the inheritance tree has diamond-inheritance structure. And, it increments > pg_attribute.attinhcount except for the first invocation. > If we store the 'expected_parents' on the ColumnDef->inhcount, we don't need > to call the ATExecAddColumn() more than once in a single ALTER TABLE command. > > Any comments? And, when should we do it? 9.0? 9.1?
The attached one also clean up ATPrepAddColumn() and ATExecAddColumn() code, not only ATPrepAlterColumnType(), according to what I mentioned above. There are two regression test fails, because it does not call ATExecAddColumn() twice or more in diamond-inheritance cases, so it does not notice merging definitions of columns. If we should go on right now, I'll add and fix regression tests, and submit a formal patch again. If not, I'll work it later. Thanks, -- OSS Platform Development Division, NEC KaiGai Kohei <kai...@ak.jp.nec.com>
pgsql-fix-inherit-attype.2.patch
Description: application/octect-stream
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