Merge with 4.0.11

BitKeeper/etc/ignore:
  auto-union
BitKeeper/etc/logging_ok:
  auto-union
BUILD/FINISH.sh:
  Auto merged
client/mysqldump.c:
  Auto merged
include/my_base.h:
  Auto merged
include/my_pthread.h:
  Auto merged
innobase/row/row0sel.c:
  Auto merged
innobase/ut/ut0mem.c:
  Auto merged
myisam/myisamchk.c:
  Auto merged
mysql-test/mysql-test-run.sh:
  Auto merged
mysql-test/r/bigint.result:
  Auto merged
mysql-test/r/handler.result:
  Auto merged
mysql-test/r/innodb.result:
  Auto merged
mysql-test/r/innodb_handler.result:
  Auto merged
mysql-test/r/query_cache.result:
  Auto merged
mysql-test/t/bigint.test:
  Auto merged
mysql-test/t/handler.test:
  Auto merged
mysql-test/t/innodb.test:
  Auto merged
mysql-test/t/innodb_handler.test:
  Auto merged
mysql-test/t/query_cache.test:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/opt_sum.cc:
  Auto merged
sql/sql_acl.cc:
  Auto merged
sql/sql_class.cc:
  Auto merged
sql/sql_handler.cc:
  Auto merged
sql/sql_load.cc:
  Auto merged
sql/sql_table.cc:
  Auto merged
sql/sql_update.cc:
  Auto merged
sql/share/czech/errmsg.txt:
  Auto merged
sql/share/danish/errmsg.txt:
  Auto merged
sql/share/dutch/errmsg.txt:
  Auto merged
sql/share/english/errmsg.txt:
  Auto merged
sql/share/estonian/errmsg.txt:
  Auto merged
sql/share/french/errmsg.txt:
  Auto merged
sql/share/greek/errmsg.txt:
  Auto merged
sql/share/hungarian/errmsg.txt:
  Auto merged
sql/share/italian/errmsg.txt:
  Auto merged
sql/share/japanese/errmsg.txt:
  Auto merged
sql/share/korean/errmsg.txt:
  Auto merged
sql/share/norwegian-ny/errmsg.txt:
  Auto merged
sql/share/norwegian/errmsg.txt:
  Auto merged
sql/share/polish/errmsg.txt:
  Auto merged
sql/share/portuguese/errmsg.txt:
  Auto merged
sql/share/romanian/errmsg.txt:
  Auto merged
sql/share/russian/errmsg.txt:
  Auto merged
sql/share/slovak/errmsg.txt:
  Auto merged
sql/share/spanish/errmsg.txt:
  Auto merged
sql/share/swedish/errmsg.txt:
  Auto merged
sql/share/ukrainian/errmsg.txt:
  Auto merged
sql/table.h:
  Auto merged

1 files changed, 15 insertions, 0 deletions

diff --git a/include/my_base.h b/include/my_base.h
index f167ae3d30e..b806436fe0e 100644
--- a/include/my_base.h
+++ b/include/my_base.h
@@ -49,6 +49,21 @@
 
 	/* The following is parameter to ha_rkey() how to use key */
 
+/* We define a complete-field prefix of a key value as a prefix where the
+last included field in the prefix contains the full field, not just some bytes
+from the start of the field. A partial-field prefix is allowed to
+contain only a few first bytes from the last included field.
+
+Below HA_READ_KEY_EXACT, ..., HA_READ_BEFORE_KEY can take a
+complete-field prefix of a key value as the search key. HA_READ_PREFIX
+and HA_READ_PREFIX_LAST could also take a partial-field prefix, but
+currently (4.0.10) they are only used with complete-field prefixes. MySQL uses
+a padding trick to implement LIKE 'abc%' queries.
+
+NOTE that in InnoDB HA_READ_PREFIX_LAST will NOT work with a partial-field
+prefix because InnoDB currently strips spaces from the end of varchar
+fields! */
+
 enum ha_rkey_function {
   HA_READ_KEY_EXACT,              /* Find first record else error */
   HA_READ_KEY_OR_NEXT,            /* Record or next record */