summaryrefslogtreecommitdiffstats
path: root/storage/myisammrg/myrg_queue.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 18:00:34 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 18:00:34 +0000
commit3f619478f796eddbba6e39502fe941b285dd97b1 (patch)
treee2c7b5777f728320e5b5542b6213fd3591ba51e2 /storage/myisammrg/myrg_queue.c
parentInitial commit. (diff)
downloadmariadb-3f619478f796eddbba6e39502fe941b285dd97b1.tar.xz
mariadb-3f619478f796eddbba6e39502fe941b285dd97b1.zip
Adding upstream version 1:10.11.6.upstream/1%10.11.6upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'storage/myisammrg/myrg_queue.c')
-rw-r--r--storage/myisammrg/myrg_queue.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/storage/myisammrg/myrg_queue.c b/storage/myisammrg/myrg_queue.c
new file mode 100644
index 00000000..08d02bd5
--- /dev/null
+++ b/storage/myisammrg/myrg_queue.c
@@ -0,0 +1,90 @@
+/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+#include "myrg_def.h"
+
+static int queue_key_cmp(void *keyseg, uchar *a, uchar *b)
+{
+ MYRG_TABLE *ma= (MYRG_TABLE *)a;
+ MYRG_TABLE *mb= (MYRG_TABLE *)b;
+ MI_INFO *aa= ma->table;
+ MI_INFO *bb= mb->table;
+ uint not_used[2];
+ int ret= ha_key_cmp((HA_KEYSEG *)keyseg, aa->lastkey, bb->lastkey,
+ USE_WHOLE_KEY, SEARCH_FIND, not_used);
+ if (ret < 0)
+ return -1;
+ if (ret > 0)
+ return 1;
+
+ /*
+ If index tuples have the same values, let the record with least rowid
+ value be "smaller", so index scans return records ordered by (keytuple,
+ rowid). This is used by index_merge access method, grep for ROR in
+ sql/opt_range.cc for details.
+ */
+ return (ma->file_offset < mb->file_offset)? -1 : (ma->file_offset >
+ mb->file_offset) ? 1 : 0;
+} /* queue_key_cmp */
+
+
+int _myrg_init_queue(MYRG_INFO *info,int inx,enum ha_rkey_function search_flag)
+{
+ int error=0;
+ QUEUE *q= &(info->by_key);
+
+ if (inx < (int) info->keys)
+ {
+ if (!is_queue_inited(q))
+ {
+ if (init_queue(q,info->tables, 0,
+ (myisam_readnext_vec[search_flag] == SEARCH_SMALLER),
+ queue_key_cmp,
+ info->open_tables->table->s->keyinfo[inx].seg, 0, 0))
+ error=my_errno;
+ }
+ else
+ {
+ if (reinit_queue(q,info->tables, 0,
+ (myisam_readnext_vec[search_flag] == SEARCH_SMALLER),
+ queue_key_cmp,
+ info->open_tables->table->s->keyinfo[inx].seg, 0, 0))
+ error=my_errno;
+ }
+ }
+ else
+ {
+ /*
+ inx may be bigger than info->keys if there are no underlying tables
+ defined. In this case we should return empty result. As we check for
+ underlying tables conformance when we open a table, we may not enter
+ this branch with underlying table that has less keys than merge table
+ have.
+ */
+ DBUG_ASSERT(!info->tables);
+ error= my_errno= HA_ERR_END_OF_FILE;
+ }
+ return error;
+}
+
+int _myrg_mi_read_record(MI_INFO *info, uchar *buf)
+{
+ if (!(*info->read_record)(info,info->lastpos,buf))
+ {
+ info->update|= HA_STATE_AKTIV; /* Record is read */
+ return 0;
+ }
+ return my_errno;
+}