Don't produce bogus COPY command when there are no undropped columns

in a table.

diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index ef000b91107fea198464f4863fc61e3e0ea8396c..e91ab42561cd2d7228e935920942bde8b4766786 100644 (file)
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -12,7 +12,7 @@
  *     by PostgreSQL
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/bin/pg_dump/pg_dump.c,v 1.310 2002/12/01 18:44:00 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/bin/pg_dump/pg_dump.c,v 1.311 2002/12/12 21:03:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -827,6 +827,9 @@ dumpClasses_nodumpData(Archive *fout, char *oid, void *dctxv)
         * possibility of retrieving data in the wrong column order.  (The
         * default column ordering of COPY will not be what we want in certain
         * corner cases involving ADD COLUMN and inheritance.)
+        *
+        * NB: caller should have already determined that there are dumpable
+        * columns, so that fmtCopyColumnList will return something.
         */
        if (g_fout->remoteVersion >= 70300)
                column_list = fmtCopyColumnList(tbinfo);
@@ -1140,40 +1143,45 @@ dumpClasses(const TableInfo *tblinfo, const int numTables, Archive *fout,
 
                if (tblinfo[i].dump)
                {
+                       const char *column_list;
+
                        if (g_verbose)
                                write_msg(NULL, "preparing to dump the contents of table %s\n",
                                                  classname);
 
-                       dumpCtx = (DumpContext *) malloc(sizeof(DumpContext));
-                       dumpCtx->tblinfo = (TableInfo *) tblinfo;
-                       dumpCtx->tblidx = i;
-                       dumpCtx->oids = oids;
-
-                       if (!dumpData)
+                       /* Get column list first to check for zero-column table */
+                       column_list = fmtCopyColumnList(&(tblinfo[i]));
+                       if (column_list)
                        {
-                               /* Dump/restore using COPY */
-                               const char *column_list;
-
-                               dumpFn = dumpClasses_nodumpData;
-                               column_list = fmtCopyColumnList(&(tblinfo[i]));
-                               resetPQExpBuffer(copyBuf);
-                               appendPQExpBuffer(copyBuf, "COPY %s %s %sFROM stdin;\n",
-                                                                 fmtId(tblinfo[i].relname),
-                                                                 column_list,
+                               dumpCtx = (DumpContext *) malloc(sizeof(DumpContext));
+                               dumpCtx->tblinfo = (TableInfo *) tblinfo;
+                               dumpCtx->tblidx = i;
+                               dumpCtx->oids = oids;
+
+                               if (!dumpData)
+                               {
+                                       /* Dump/restore using COPY */
+                                       dumpFn = dumpClasses_nodumpData;
+                                       resetPQExpBuffer(copyBuf);
+                                       appendPQExpBuffer(copyBuf, "COPY %s %s %sFROM stdin;\n",
+                                                                         fmtId(tblinfo[i].relname),
+                                                                         column_list,
                                           (oids && tblinfo[i].hasoids) ? "WITH OIDS " : "");
-                               copyStmt = copyBuf->data;
-                       }
-                       else
-                       {
-                               /* Restore using INSERT */
-                               dumpFn = dumpClasses_dumpData;
-                               copyStmt = NULL;
-                       }
+                                       copyStmt = copyBuf->data;
+                               }
+                               else
+                               {
+                                       /* Restore using INSERT */
+                                       dumpFn = dumpClasses_dumpData;
+                                       copyStmt = NULL;
+                               }
 
-                       ArchiveEntry(fout, tblinfo[i].oid, tblinfo[i].relname,
-                                       tblinfo[i].relnamespace->nspname, tblinfo[i].usename,
-                                                "TABLE DATA", NULL, "", "", copyStmt,
-                                                dumpFn, dumpCtx);
+                               ArchiveEntry(fout, tblinfo[i].oid, tblinfo[i].relname,
+                                                        tblinfo[i].relnamespace->nspname,
+                                                        tblinfo[i].usename,
+                                                        "TABLE DATA", NULL, "", "", copyStmt,
+                                                        dumpFn, dumpCtx);
+                       }
                }
        }
 
@@ -3220,13 +3228,16 @@ dumpOneDomain(Archive *fout, TypeInfo *tinfo)
        if (typdefault)
                appendPQExpBuffer(q, " DEFAULT %s", typdefault);
 
-       /* Fetch and process CHECK Constraints */
+       PQclear(res);
+
+       /*
+        * Fetch and process CHECK constraints for the domain
+        */
        appendPQExpBuffer(chkquery, "SELECT conname, consrc "
                                          "FROM pg_catalog.pg_constraint "
                                          "WHERE contypid = '%s'::pg_catalog.oid",
                                          tinfo->oid);
 
-       PQclear(res);
        res = PQexec(g_conn, chkquery->data);
        if (!res ||
                PQresultStatus(res) != PGRES_TUPLES_OK)
@@ -3236,7 +3247,6 @@ dumpOneDomain(Archive *fout, TypeInfo *tinfo)
                exit_nicely();
        }
 
-       /* Expecting a single result only */
        ntups = PQntuples(res);
        for (i = 0; i < ntups; i++)
        {
@@ -3246,7 +3256,8 @@ dumpOneDomain(Archive *fout, TypeInfo *tinfo)
                conname = PQgetvalue(res, i, PQfnumber(res, "conname"));
                consrc = PQgetvalue(res, i, PQfnumber(res, "consrc"));
 
-               appendPQExpBuffer(q, " CONSTRAINT %s CHECK %s", fmtId(conname), consrc);
+               appendPQExpBuffer(q, "\n\tCONSTRAINT %s CHECK %s",
+                                                 fmtId(conname), consrc);
        }
        
        appendPQExpBuffer(q, ";\n");
@@ -6744,7 +6755,10 @@ fmtQualifiedId(const char *schema, const char *id)
 }
 
 /*
- * return a column list clause for the given relation.
+ * Return a column list clause for the given relation.
+ *
+ * Special case: if there are no undropped columns in the relation, return
+ * NULL, not an invalid "()" column list.
  */
 static const char *
 fmtCopyColumnList(const TableInfo *ti)
@@ -6772,6 +6786,10 @@ fmtCopyColumnList(const TableInfo *ti)
                appendPQExpBuffer(q, "%s", fmtId(attnames[i]));
                needComma = true;
        }
+
+       if (!needComma)
+               return NULL;                    /* no undropped columns */
+
        appendPQExpBuffer(q, ")");
        return q->data;
 }