MDEV-10139 Support for SEQUENCE objects

Working features:
CREATE OR REPLACE [TEMPORARY] SEQUENCE [IF NOT EXISTS] name
    [ INCREMENT [ BY | = ] increment ]
    [ MINVALUE [=] minvalue | NO MINVALUE ]
    [ MAXVALUE [=] maxvalue | NO MAXVALUE ]
    [ START [ WITH | = ] start ] [ CACHE [=] cache ] [ [ NO ] CYCLE ]
    ENGINE=xxx COMMENT=".."
SELECT NEXT VALUE FOR sequence_name;
SELECT NEXTVAL(sequence_name);
SELECT PREVIOUS VALUE FOR sequence_name;
SELECT LASTVAL(sequence_name);

SHOW CREATE SEQUENCE sequence_name;
SHOW CREATE TABLE sequence_name;
CREATE TABLE sequence-structure ... SEQUENCE=1
ALTER TABLE sequence RENAME TO sequence2;
RENAME TABLE sequence TO sequence2;
DROP [TEMPORARY] SEQUENCE  [IF EXISTS] sequence_names

Missing features
- SETVAL(value,sequence_name), to be used with replication.
- Check replication, including checking that sequence tables are marked
  not transactional.
- Check that a commit happens for NEXT VALUE that changes table data (may
  already work)
- ALTER SEQUENCE. ANSI SQL version of setval.
- Share identical sequence entries to not add things twice to table list.
- testing insert/delete/update/truncate/load data
- Run and fix Alibaba sequence tests (part of mysql-test/suite/sql_sequence)
- Write documentation for NEXT VALUE / PREVIOUS_VALUE
- NEXTVAL in DEFAULT
  - Ensure that NEXTVAL in DEFAULT uses database from base table
- Two NEXTVAL for same row should give same answer.
- Oracle syntax sequence_table.nextval, without any FOR or FROM.
- Sequence tables are treated as 'not read constant tables' by SELECT; Would
  be better if we would have a separate list for sequence tables so that
  select doesn't know about them, except if refereed to with FROM.

Other things done:
- Improved output for safemalloc backtrack
- frm_type_enum changed to Table_type
- Removed lex->is_view and replaced with lex->table_type. This allows
  use to more easy check if item is view, sequence or table.
- Added table flag HA_CAN_TABLES_WITHOUT_ROLLBACK, needed for handlers
  that want's to support sequences
- Added handler calls:
 - engine_name(), to simplify getting engine name for partition and sequences
 - update_first_row(), to be able to do efficient sequence implementations.
 - Made binlog_log_row() global to be able to call it from ha_sequence.cc
- Added handler variable: row_already_logged, to be able to flag that the
  changed row is already logging to replication log.
- Added CF_DB_CHANGE and CF_SCHEMA_CHANGE flags to simplify
  deny_updates_if_read_only_option()
- Added sp_add_cfetch() to avoid new conflicts in sql_yacc.yy
- Moved code for add_table_options() out from sql_show.cc::show_create_table()
- Added String::append_longlong() and used it in sql_show.cc to simplify code.
- Added extra option to dd_frm_type() and ha_table_exists to indicate if
  the table is a sequence. Needed by DROP SQUENCE to not drop a table.

1 files changed, 6 insertions, 2 deletions

diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index a9c89aef0a8..aeaca82649f 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -234,12 +234,14 @@ sp_get_flags_for_command(LEX *lex)
     flags= sp_head::CONTAINS_DYNAMIC_SQL;
     break;
   case SQLCOM_CREATE_TABLE:
+  case SQLCOM_CREATE_SEQUENCE:
     if (lex->tmp_table())
       flags= 0;
     else
       flags= sp_head::HAS_COMMIT_OR_ROLLBACK;
     break;
   case SQLCOM_DROP_TABLE:
+  case SQLCOM_DROP_SEQUENCE:
     if (lex->tmp_table())
       flags= 0;
     else
@@ -4407,7 +4409,8 @@ sp_head::merge_table_list(THD *thd, TABLE_LIST *table, LEX *lex_for_tmp_check)
 {
   SP_TABLE *tab;
 
-  if (lex_for_tmp_check->sql_command == SQLCOM_DROP_TABLE &&
+  if ((lex_for_tmp_check->sql_command == SQLCOM_DROP_TABLE ||
+      lex_for_tmp_check->sql_command == SQLCOM_DROP_SEQUENCE) &&
       lex_for_tmp_check->tmp_table())
     return TRUE;
 
@@ -4471,7 +4474,8 @@ sp_head::merge_table_list(THD *thd, TABLE_LIST *table, LEX *lex_for_tmp_check)
       {
         if (!(tab= (SP_TABLE *)thd->calloc(sizeof(SP_TABLE))))
           return FALSE;
-        if (lex_for_tmp_check->sql_command == SQLCOM_CREATE_TABLE &&
+        if ((lex_for_tmp_check->sql_command == SQLCOM_CREATE_TABLE ||
+             lex_for_tmp_check->sql_command == SQLCOM_CREATE_SEQUENCE) &&
             lex_for_tmp_check->query_tables == table &&
             lex_for_tmp_check->tmp_table())
         {