Support SERIAL column type. Expand column marked is_sequence into three

 statements:
 - the table definition with a default clause referencing the sequence;
 - a CREATE SEQUENCE statement;
 - a UNIQUE constraint, which expands into a CREATE INDEX statement.
This is not a perfect solution, since the sequence will remain even if
 the table is dropped. Also, there is no absolute protection on updating
 the sequence column.

diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 2bdcef170f3ea72478ec2b500e295c5c456cbebe..ea96f2eb91069e43c6215bb5f3d237b5592f5cb6 100644 (file)
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.80 1998/08/18 00:48:54 scrappy Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.81 1998/08/25 15:08:12 thomas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -472,7 +472,7 @@ transformCreateStmt(ParseState *pstate, CreateStmt *stmt)
    Constraint *constraint;
    List       *keys;
    Ident      *key;
-   List       *ilist;
+   List       *ilist = NIL;
    IndexStmt  *index;
    IndexElem  *iparam;
 
@@ -492,6 +492,46 @@ transformCreateStmt(ParseState *pstate, CreateStmt *stmt)
            case T_ColumnDef:
                column = (ColumnDef *) element;
                columns = lappend(columns, column);
+
+               if (column->is_sequence)
+               {
+                   char *cstring;
+                   CreateSeqStmt *sequence;
+
+                   constraint = makeNode(Constraint);
+                   constraint->contype = CONSTR_DEFAULT;
+                   constraint->name = makeTableName(stmt->relname, column->colname, "seq", NULL);
+                   cstring = palloc(9+strlen(constraint->name)+2+1);
+                   strcpy(cstring, "nextval('");
+                   strcat(cstring, constraint->name);
+                   strcat(cstring, "')");
+                   constraint->def = cstring;
+                   constraint->keys = NULL;
+
+                   if (column->constraints != NIL)
+                   {
+                       column->constraints = lappend(column->constraints, constraint);
+                   }
+                   else
+                   {
+                       column->constraints = lcons(constraint, NIL);
+                   }
+
+                   sequence = makeNode(CreateSeqStmt);
+                   sequence->seqname = constraint->name;
+                   sequence->options = NIL;
+
+                   elog(NOTICE, "CREATE TABLE will create implicit sequence %s for SERIAL column %s.%s",
+                        sequence->seqname, stmt->relname, column->colname);
+
+                   ilist = lcons(sequence, NIL);
+
+                   constraint = makeNode(Constraint);
+                   constraint->contype = CONSTR_UNIQUE;
+
+                   column->constraints = lappend(column->constraints, constraint);
+               }
+
                if (column->constraints != NIL)
                {
                    clist = column->constraints;
@@ -596,7 +636,6 @@ transformCreateStmt(ParseState *pstate, CreateStmt *stmt)
  * names for indices turn out to be redundant, or a user might have specified
  * extra useless indices which might hurt performance. - thomas 1997-12-08
  */
-   ilist = NIL;
    while (dlist != NIL)
    {
        constraint = lfirst(dlist);