Code review for patch to show definition of index columns in \d on index.

Safely schema-qualify the pg_get_indexdef call, make the query a bit
prettier in -E mode, remove useless join to pg_index, make it more obvious
that the header[] array is not overrun.

diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index 0eb77fe6f1964924bc2e93880a97a98f44908a63..be864780a648d6dff49b59486204d3fff77cc43b 100644 (file)
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -8,7 +8,7 @@
  *
  * Copyright (c) 2000-2009, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/bin/psql/describe.c,v 1.220 2009/07/06 17:01:42 petere Exp $
+ * $PostgreSQL: pgsql/src/bin/psql/describe.c,v 1.221 2009/07/07 16:28:38 tgl Exp $
  */
 #include "postgres_fe.h"
 
@@ -1028,7 +1028,7 @@ describeOneTableDetails(const char *schemaname,
    char      **ptr;
    PQExpBufferData title;
    PQExpBufferData tmpbuf;
-   int         cols = 0;
+   int         cols;
    int         numrows = 0;
    struct
    {
@@ -1156,7 +1156,7 @@ describeOneTableDetails(const char *schemaname,
        PQclear(result);
    }
 
-   /* Get column info (index requires additional checks) */
+   /* Get column info */
    printfPQExpBuffer(&buf, "SELECT a.attname,");
    appendPQExpBuffer(&buf, "\n  pg_catalog.format_type(a.atttypid, a.atttypmod),"
                      "\n  (SELECT substring(pg_catalog.pg_get_expr(d.adbin, d.adrelid) for 128)"
@@ -1164,15 +1164,11 @@ describeOneTableDetails(const char *schemaname,
                      "\n   WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef),"
                      "\n  a.attnotnull, a.attnum");
    if (tableinfo.relkind == 'i')
-       appendPQExpBuffer(&buf, ", pg_get_indexdef(i.indexrelid,a.attnum, TRUE) AS indexdef");
+       appendPQExpBuffer(&buf, ",\n  pg_catalog.pg_get_indexdef(a.attrelid, a.attnum, TRUE) AS indexdef");
    if (verbose)
-       appendPQExpBuffer(&buf, ", a.attstorage, pg_catalog.col_description(a.attrelid, a.attnum)");
+       appendPQExpBuffer(&buf, ",\n  a.attstorage, pg_catalog.col_description(a.attrelid, a.attnum)");
    appendPQExpBuffer(&buf, "\nFROM pg_catalog.pg_attribute a");
-   if (tableinfo.relkind == 'i')
-       appendPQExpBuffer(&buf, ", pg_catalog.pg_index i");
    appendPQExpBuffer(&buf, "\nWHERE a.attrelid = '%s' AND a.attnum > 0 AND NOT a.attisdropped", oid);
-   if (tableinfo.relkind == 'i')
-       appendPQExpBuffer(&buf, " AND a.attrelid = i.indexrelid");
    appendPQExpBuffer(&buf, "\nORDER BY a.attnum");
 
    res = PSQLexec(buf.data, false);
@@ -1220,9 +1216,9 @@ describeOneTableDetails(const char *schemaname,
    }
 
    /* Set the number of columns, and their names */
-   cols += 2;
    headers[0] = gettext_noop("Column");
    headers[1] = gettext_noop("Type");
+   cols = 2;
 
    if (tableinfo.relkind == 'r' || tableinfo.relkind == 'v')
    {
@@ -1302,15 +1298,15 @@ describeOneTableDetails(const char *schemaname,
        if (tableinfo.relkind == 'S')
            printTableAddCell(&cont, seq_values[i], false);
 
-       /* Expression for index */
+       /* Expression for index column */
        if (tableinfo.relkind == 'i')
            printTableAddCell(&cont, PQgetvalue(res, i, 5), false);
 
        /* Storage and Description */
        if (verbose)
        {
-           int fnum = (tableinfo.relkind == 'i' ? 6 : 5);
-           char       *storage  = PQgetvalue(res, i, fnum);
+           int         firstvcol = (tableinfo.relkind == 'i' ? 6 : 5);
+           char       *storage  = PQgetvalue(res, i, firstvcol);
 
            /* these strings are literal in our syntax, so not translated. */
            printTableAddCell(&cont, (storage[0] == 'p' ? "plain" :
@@ -1319,7 +1315,7 @@ describeOneTableDetails(const char *schemaname,
                                        (storage[0] == 'e' ? "external" :
                                         "???")))),
                              false);
-           printTableAddCell(&cont, PQgetvalue(res, i, fnum + 1), false);
+           printTableAddCell(&cont, PQgetvalue(res, i, firstvcol + 1), false);
        }
    }
 
@@ -1844,20 +1840,23 @@ describeOneTableDetails(const char *schemaname,
        }
        else
        {
-           /* display the list of child tables*/
+           /* display the list of child tables */
+           const char *ct = _("Child tables");
+
            for (i = 0; i < tuples; i++)
-                   {
-                           const char *ct = _("Child tables");
-
-                           if (i == 0)
-                                   printfPQExpBuffer(&buf, "%s: %s", ct, PQgetvalue(result, i, 0));
-                           else
-                                   printfPQExpBuffer(&buf, "%*s  %s", (int) strlen(ct), "", PQgetvalue(result, i, 0));
-                           if (i < tuples - 1)
-                                   appendPQExpBuffer(&buf, ",");
-
-                           printTableAddFooter(&cont, buf.data);
-                   }
+           {
+               if (i == 0)
+                   printfPQExpBuffer(&buf, "%s: %s",
+                                     ct, PQgetvalue(result, i, 0));
+               else
+                   printfPQExpBuffer(&buf, "%*s  %s",
+                                     (int) strlen(ct), "",
+                                     PQgetvalue(result, i, 0));
+               if (i < tuples - 1)
+                   appendPQExpBuffer(&buf, ",");
+
+               printTableAddFooter(&cont, buf.data);
+           }
        }
        PQclear(result);