1 files changed, 62 insertions, 13 deletions

diff --git a/innobase/row/row0sel.c b/innobase/row/row0sel.c
index abae7f373bf..f3dced15fdf 100644
--- a/innobase/row/row0sel.c
+++ b/innobase/row/row0sel.c
@@ -2071,13 +2071,11 @@ row_sel_store_mysql_rec(
 		data = rec_get_nth_field(rec, templ->rec_field_no, &len);
 
 		if (rec_get_nth_field_extern_bit(rec, templ->rec_field_no)) {
+
 			/* Copy an externally stored field to the temporary
 			heap */
 
-			if (prebuilt->trx->has_search_latch) {
-				rw_lock_s_unlock(&btr_search_latch);
-				prebuilt->trx->has_search_latch = FALSE;
-			}
+			ut_a(!prebuilt->trx->has_search_latch);
 
 			extern_field_heap = mem_heap_create(UNIV_PAGE_SIZE);
 
@@ -2091,6 +2089,8 @@ row_sel_store_mysql_rec(
 		if (len != UNIV_SQL_NULL) {
 			if (templ->type == DATA_BLOB) {
 
+				ut_a(prebuilt->templ_contains_blob);
+				
 				/* Copy the BLOB data to the BLOB
 				heap of prebuilt */
 
@@ -2116,8 +2116,28 @@ row_sel_store_mysql_rec(
 				extern_field_heap = NULL;
  			}
 		} else {
-			mysql_rec[templ->mysql_null_byte_offset] |=
+			/* MySQL sometimes seems to copy the 'data'
+			pointed to by a BLOB field even if the field
+			has been marked to contain the SQL NULL value.
+			This caused seg faults reported by two users.
+			Set the BLOB length to 0 and the data pointer
+			to NULL to avoid a seg fault. */
+
+			if (templ->type == DATA_BLOB) {
+				row_sel_field_store_in_mysql_format(
+				mysql_rec + templ->mysql_col_offset,
+				templ->mysql_col_len, NULL,
+				0, templ->type, templ->is_unsigned);
+			}
+
+			if (!templ->mysql_null_bit_mask) {
+				fprintf(stderr,
+"InnoDB: Error: trying to return an SQL NULL field in a non-null\n"
+"innoDB: column! Table name %s\n", prebuilt->table->name);
+			} else {
+				mysql_rec[templ->mysql_null_byte_offset] |=
 					(byte) (templ->mysql_null_bit_mask);
+			}
 		}
 	} 
 }
@@ -2234,7 +2254,7 @@ row_sel_get_clust_rec_for_mysql(
 		(or old_vers) is not rec; in that case we must ignore
 		such row because in our snapshot rec would not have existed.
 		Remember that from rec we cannot see directly which transaction
-		id corrsponds to it: we have to go to the clustered index
+		id corresponds to it: we have to go to the clustered index
 		record. A query where we want to fetch all rows where
 		the secondary index value is in some interval would return
 		a wrong result if we would not drop rows which we come to
@@ -2245,6 +2265,12 @@ row_sel_get_clust_rec_for_mysql(
 		    && !row_sel_sec_rec_is_for_clust_rec(rec, sec_index,
 						clust_rec, clust_index)) {
 			clust_rec = NULL;
+		} else {
+#ifdef UNIV_SEARCH_DEBUG
+			ut_a(clust_rec == NULL ||
+			    row_sel_sec_rec_is_for_clust_rec(rec, sec_index,
+						clust_rec, clust_index));
+#endif		
 		}
 	}
 
@@ -2357,6 +2383,7 @@ row_sel_push_cache_row_for_mysql(
 	ulint	i;
 
 	ut_ad(prebuilt->n_fetch_cached < MYSQL_FETCH_CACHE_SIZE);
+	ut_a(!prebuilt->templ_contains_blob);
 
 	if (prebuilt->fetch_cache[0] == NULL) {
 		/* Allocate memory for the fetch cache */
@@ -2397,10 +2424,16 @@ row_sel_try_search_shortcut_for_mysql(
 	rec_t*		rec;
 	
 	ut_ad(index->type & DICT_CLUSTERED);
+	ut_ad(!prebuilt->templ_contains_blob);
 
 	btr_pcur_open_with_no_init(index, search_tuple, PAGE_CUR_GE,
 					BTR_SEARCH_LEAF, pcur,
-					RW_S_LATCH, mtr);
+#ifndef UNIV_SEARCH_DEBUG
+					RW_S_LATCH,
+#else
+					0,
+#endif
+					mtr);
 	rec = btr_pcur_get_rec(pcur);
 	
 	if (!page_rec_is_user_rec(rec)) {
@@ -2574,8 +2607,16 @@ row_search_for_mysql(
 
 	mtr_start(&mtr);
 
-	if (match_mode == ROW_SEL_EXACT && index->type & DICT_UNIQUE
+	/* Since we must release the search system latch when we retrieve an
+	externally stored field, we cannot use the adaptive hash index in a
+	search in the case the row may be long and there may be externally
+	stored fields */
+	
+	if (match_mode == ROW_SEL_EXACT
+		&& index->type & DICT_UNIQUE
 		&& index->type & DICT_CLUSTERED
+		&& !prebuilt->templ_contains_blob
+		&& (prebuilt->mysql_row_len < UNIV_PAGE_SIZE / 8)
 		&& dtuple_get_n_fields(search_tuple)
 				== dict_index_get_n_unique(index)) {
 
@@ -2624,15 +2665,18 @@ row_search_for_mysql(
 				
 				goto no_shortcut;
 			}
-			
+#ifndef UNIV_SEARCH_DEBUG			
 			if (!trx->has_search_latch) {
 				rw_lock_s_lock(&btr_search_latch);
 				trx->has_search_latch = TRUE;
 			}
-
+#endif
 			shortcut = row_sel_try_search_shortcut_for_mysql(&rec,
 							       prebuilt, &mtr);
 			if (shortcut == SEL_FOUND) {
+#ifdef UNIV_SEARCH_DEBUG
+				ut_a(0 == cmp_dtuple_rec(search_tuple, rec));
+#endif 
 				row_sel_store_mysql_rec(buf, prebuilt, rec);
 	
  				mtr_commit(&mtr);
@@ -2794,7 +2838,9 @@ rec_loop:
 		/* The record matches enough */
 
 		ut_ad(mode == PAGE_CUR_GE);
-	
+#ifdef UNIV_SEARCH_DEBUG
+		ut_a(0 == cmp_dtuple_rec(search_tuple, rec));
+#endif	
 	} else if (match_mode == ROW_SEL_EXACT) {
 		/* Test if the index record matches completely to search_tuple
 		in prebuilt: if not, then we return with DB_RECORD_NOT_FOUND */
@@ -2923,15 +2969,18 @@ rec_loop:
 	/* We found a qualifying row */
 	
 	if (prebuilt->n_rows_fetched >= MYSQL_FETCH_CACHE_THRESHOLD
-			&& !prebuilt->templ_contains_blob
 			&& prebuilt->select_lock_type == LOCK_NONE
+			&& !prebuilt->templ_contains_blob
 			&& !prebuilt->clust_index_was_generated
 	                && prebuilt->template_type
 	                                 != ROW_MYSQL_DUMMY_TEMPLATE) {
 
 		/* Inside an update, for example, we do not cache rows,
 		since we may use the cursor position to do the actual
-		update, that is why we require ...lock_type == LOCK_NONE */
+		update, that is why we require ...lock_type == LOCK_NONE.
+		Since we keep space in prebuilt only for the BLOBs of
+		a single row, we cannot cache rows in the case there
+		are BLOBs in the fields to be fetched. */
 
 		row_sel_push_cache_row_for_mysql(prebuilt, rec);