ha_innobase.cc:

  Backport from 4.0: Fix bug in MySQL-3.23 ORDER BY from a table with no PRIMARY KEY and where the user had added UNIQUE indexes with CREATE INDEX
pars0grm.y:
  Move inclusion of math.h after univ.i also in the .y file; this fix is already done in 4.0

innobase/pars/pars0grm.y

@@ -14,9 +14,8 @@ the InnoDB parser.
 /* The value of the semantic attribute is a pointer to a query tree node
 que_node_t */
 
-#include <math.h>
-
 #include "univ.i"
+#include <math.h>
 #include "pars0pars.h"
 #include "mem0mem.h"
 #include "que0types.h"

sql/ha_innobase.cc

@@ -993,7 +993,10 @@ how you can resolve the problem.\n",
 
 	((row_prebuilt_t*)innobase_prebuilt)->mysql_row_len = table->reclength;
 
-  	primary_key = MAX_KEY;
+	/* Looks like MySQL-3.23 sometimes has primary key number != 0 */
+
+ 	primary_key = table->primary_key;
+	key_used_on_scan = primary_key;
 
 	/* Allocate a buffer for a 'row reference'. A row reference is
 	a string of bytes of length ref_length which uniquely specifies
@@ -1002,21 +1005,30 @@ how you can resolve the problem.\n",
         of length ref_length! */
 
   	if (!row_table_got_default_clust_index(ib_table)) {
+	        if (primary_key >= MAX_KEY) {
+	                fprintf(stderr,
+		    "InnoDB: Error: table %s has a primary key in InnoDB\n"
+		    "InnoDB: data dictionary, but not in MySQL!\n", name);
+		}
 
 		((row_prebuilt_t*)innobase_prebuilt)
 				->clust_index_was_generated = FALSE;
-
-		primary_key = 0;
-		key_used_on_scan = 0;
-
- 		/* MySQL allocates the buffer for ref. key_info->key_length
+ 		/*
+		  MySQL allocates the buffer for ref. key_info->key_length
 		  includes space for all key columns + one byte for each column
 		  that may be NULL. ref_length must be as exact as possible to
 		  save space, because all row reference buffers are allocated
-		based on ref_length. */
+		  based on ref_length.
+		*/
  
-  		ref_length = table->key_info->key_length;
+  		ref_length = table->key_info[primary_key].key_length;
 	} else {
+	        if (primary_key != MAX_KEY) {
+	                fprintf(stderr,
+		    "InnoDB: Error: table %s has no primary key in InnoDB\n"
+		    "InnoDB: data dictionary, but has one in MySQL!\n", name);
+		}
+
 		((row_prebuilt_t*)innobase_prebuilt)
 				->clust_index_was_generated = TRUE;