Re: Bug #896: Column Constraint Not Working in ALTER TABLE ADD COLUMN? - Mailing list pgsql-bugs

pgsql-bugs@postgresql.org writes:
> Column Constraint Not Working in ALTER TABLE ADD COLUMN?

Yeah, the parser was losing foreign key constraints in this case :-(
Patch against 7.3 is attached.

            regards, tom lane

*** src/backend/parser/analyze.c.orig    Mon Feb 10 23:13:39 2003
--- src/backend/parser/analyze.c    Thu Feb 13 17:41:13 2003
***************
*** 111,117 ****
  static void transformIndexConstraints(ParseState *pstate,
                            CreateStmtContext *cxt);
  static void transformFKConstraints(ParseState *pstate,
!                        CreateStmtContext *cxt);
  static void applyColumnNames(List *dst, List *src);
  static List *getSetColTypes(ParseState *pstate, Node *node);
  static void transformForUpdate(Query *qry, List *forUpdate);
--- 111,118 ----
  static void transformIndexConstraints(ParseState *pstate,
                            CreateStmtContext *cxt);
  static void transformFKConstraints(ParseState *pstate,
!                                    CreateStmtContext *cxt,
!                                    bool isAddConstraint);
  static void applyColumnNames(List *dst, List *src);
  static List *getSetColTypes(ParseState *pstate, Node *node);
  static void transformForUpdate(Query *qry, List *forUpdate);
***************
*** 770,776 ****
      /*
       * Postprocess foreign-key constraints.
       */
!     transformFKConstraints(pstate, &cxt);

      /*
       * Output results.
--- 771,777 ----
      /*
       * Postprocess foreign-key constraints.
       */
!     transformFKConstraints(pstate, &cxt, false);

      /*
       * Output results.
***************
*** 1296,1302 ****
  }

  static void
! transformFKConstraints(ParseState *pstate, CreateStmtContext *cxt)
  {
      if (cxt->fkconstraints == NIL)
          return;
--- 1297,1304 ----
  }

  static void
! transformFKConstraints(ParseState *pstate, CreateStmtContext *cxt,
!                        bool isAddConstraint)
  {
      if (cxt->fkconstraints == NIL)
          return;
***************
*** 1305,1320 ****
           cxt->stmtType);

      /*
!      * For ALTER TABLE ADD CONSTRAINT, nothing to do.  For CREATE TABLE,
!      * gin up an ALTER TABLE ADD CONSTRAINT command to execute after
!      * the basic CREATE TABLE is complete.
       *
       * Note: the ADD CONSTRAINT command must also execute after any index
       * creation commands.  Thus, this should run after
       * transformIndexConstraints, so that the CREATE INDEX commands are
       * already in cxt->alist.
       */
!     if (strcmp(cxt->stmtType, "CREATE TABLE") == 0)
      {
          AlterTableStmt *alterstmt = makeNode(AlterTableStmt);
          List       *fkclist;
--- 1307,1322 ----
           cxt->stmtType);

      /*
!      * For ALTER TABLE ADD CONSTRAINT, nothing to do.  For CREATE TABLE or
!      * ALTER TABLE ADD COLUMN, gin up an ALTER TABLE ADD CONSTRAINT command
!      * to execute after the basic command is complete.
       *
       * Note: the ADD CONSTRAINT command must also execute after any index
       * creation commands.  Thus, this should run after
       * transformIndexConstraints, so that the CREATE INDEX commands are
       * already in cxt->alist.
       */
!     if (!isAddConstraint)
      {
          AlterTableStmt *alterstmt = makeNode(AlterTableStmt);
          List       *fkclist;
***************
*** 2253,2259 ****
                                        (ColumnDef *) stmt->def);

              transformIndexConstraints(pstate, &cxt);
!             transformFKConstraints(pstate, &cxt);

              ((ColumnDef *) stmt->def)->constraints = cxt.ckconstraints;
              *extras_before = nconc(*extras_before, cxt.blist);
--- 2255,2261 ----
                                        (ColumnDef *) stmt->def);

              transformIndexConstraints(pstate, &cxt);
!             transformFKConstraints(pstate, &cxt, false);

              ((ColumnDef *) stmt->def)->constraints = cxt.ckconstraints;
              *extras_before = nconc(*extras_before, cxt.blist);
***************
*** 2290,2298 ****
                  elog(ERROR, "Unexpected node type in ALTER TABLE ADD CONSTRAINT");

              transformIndexConstraints(pstate, &cxt);
!             transformFKConstraints(pstate, &cxt);

              Assert(cxt.columns == NIL);
              stmt->def = (Node *) nconc(cxt.ckconstraints, cxt.fkconstraints);
              *extras_before = nconc(*extras_before, cxt.blist);
              *extras_after = nconc(cxt.alist, *extras_after);
--- 2292,2301 ----
                  elog(ERROR, "Unexpected node type in ALTER TABLE ADD CONSTRAINT");

              transformIndexConstraints(pstate, &cxt);
!             transformFKConstraints(pstate, &cxt, true);

              Assert(cxt.columns == NIL);
+             /* fkconstraints should be put into my own stmt in this case */
              stmt->def = (Node *) nconc(cxt.ckconstraints, cxt.fkconstraints);
              *extras_before = nconc(*extras_before, cxt.blist);
              *extras_after = nconc(cxt.alist, *extras_after);