MDEV-371 Unique Index for long columns
This patch implements engine independent unique hash index.
Usage:- Unique HASH index can be created automatically for blob/varchar/test column whose key
length > handler->max_key_length()
or it can be explicitly specified.
Automatic Creation:-
Create TABLE t1 (a blob unique);
Explicit Creation:-
Create TABLE t1 (a int , unique(a) using HASH);
Internal KEY_PART Representations:-
Long unique key_info will have 2 representations.
(lets understand this with an example create table t1(a blob, b blob , unique(a, b)); )
1. User Given Representation:- key_info->key_part array will be similar to what user has defined.
So in case of example it will have 2 key_parts (a, b)
2. Storage Engine Representation:- In this case there will be only one key_part and it will point to
HASH_FIELD. This key_part will be always after user defined key_parts.
So:- User Given Representation [a] [b] [hash_key_part]
key_info->key_part ----^
Storage Engine Representation [a] [b] [hash_key_part]
key_info->key_part ------------^
Table->s->key_info will have User Given Representation, While table->key_info will have Storage Engine
Representation.Representation can be changed into each other by calling re/setup_keyinfo_hash function.
Working:-
1. So when user specifies HASH_INDEX or key_length is > handler->max_key_length(), In mysql_prepare_create_table
One extra vfield is added (for each long unique key). And key_info->algorithm is set to HA_KEY_ALG_LONG_HASH.
2. In init_from_binary_frm_image values for hash_keypart is set (like fieldnr , field and flags)
3. In parse_vcol_defs, HASH_FIELD->vcol_info is created. Item_func_hash is used with list of Item_fields,
When Explicit length is given by user then Item_left is used to concatenate Item_field values.
4. In ha_write_row/ha_update_row check_duplicate_long_entry_key is called which will create the hash key from
table->record[0] and then call ha_index_read_map , if we found duplicated hash , we will compare the result
field by field.
2019-02-19 22:23:08 +01:00
|
|
|
--source include/have_innodb.inc
|
|
|
|
|
|
2019-02-21 22:42:00 +01:00
|
|
|
#
|
|
|
|
|
# MDEV-371 Unique indexes for blobs
|
|
|
|
|
#
|
|
|
|
|
|
MDEV-371 Unique Index for long columns
This patch implements engine independent unique hash index.
Usage:- Unique HASH index can be created automatically for blob/varchar/test column whose key
length > handler->max_key_length()
or it can be explicitly specified.
Automatic Creation:-
Create TABLE t1 (a blob unique);
Explicit Creation:-
Create TABLE t1 (a int , unique(a) using HASH);
Internal KEY_PART Representations:-
Long unique key_info will have 2 representations.
(lets understand this with an example create table t1(a blob, b blob , unique(a, b)); )
1. User Given Representation:- key_info->key_part array will be similar to what user has defined.
So in case of example it will have 2 key_parts (a, b)
2. Storage Engine Representation:- In this case there will be only one key_part and it will point to
HASH_FIELD. This key_part will be always after user defined key_parts.
So:- User Given Representation [a] [b] [hash_key_part]
key_info->key_part ----^
Storage Engine Representation [a] [b] [hash_key_part]
key_info->key_part ------------^
Table->s->key_info will have User Given Representation, While table->key_info will have Storage Engine
Representation.Representation can be changed into each other by calling re/setup_keyinfo_hash function.
Working:-
1. So when user specifies HASH_INDEX or key_length is > handler->max_key_length(), In mysql_prepare_create_table
One extra vfield is added (for each long unique key). And key_info->algorithm is set to HA_KEY_ALG_LONG_HASH.
2. In init_from_binary_frm_image values for hash_keypart is set (like fieldnr , field and flags)
3. In parse_vcol_defs, HASH_FIELD->vcol_info is created. Item_func_hash is used with list of Item_fields,
When Explicit length is given by user then Item_left is used to concatenate Item_field values.
4. In ha_write_row/ha_update_row check_duplicate_long_entry_key is called which will create the hash key from
table->record[0] and then call ha_index_read_map , if we found duplicated hash , we will compare the result
field by field.
2019-02-19 22:23:08 +01:00
|
|
|
create table t1(a blob unique) engine= InnoDB;
|
|
|
|
|
insert into t1 values('RUC');
|
|
|
|
|
--error ER_DUP_ENTRY
|
|
|
|
|
insert into t1 values ('RUC');
|
|
|
|
|
drop table t1;
|
|
|
|
|
|
2019-02-21 22:42:00 +01:00
|
|
|
create table t1 (a blob unique , c int unique) engine=innodb;
|
|
|
|
|
show create table t1;
|
|
|
|
|
drop table t1;
|
|
|
|
|
|
MDEV-371 Unique Index for long columns
This patch implements engine independent unique hash index.
Usage:- Unique HASH index can be created automatically for blob/varchar/test column whose key
length > handler->max_key_length()
or it can be explicitly specified.
Automatic Creation:-
Create TABLE t1 (a blob unique);
Explicit Creation:-
Create TABLE t1 (a int , unique(a) using HASH);
Internal KEY_PART Representations:-
Long unique key_info will have 2 representations.
(lets understand this with an example create table t1(a blob, b blob , unique(a, b)); )
1. User Given Representation:- key_info->key_part array will be similar to what user has defined.
So in case of example it will have 2 key_parts (a, b)
2. Storage Engine Representation:- In this case there will be only one key_part and it will point to
HASH_FIELD. This key_part will be always after user defined key_parts.
So:- User Given Representation [a] [b] [hash_key_part]
key_info->key_part ----^
Storage Engine Representation [a] [b] [hash_key_part]
key_info->key_part ------------^
Table->s->key_info will have User Given Representation, While table->key_info will have Storage Engine
Representation.Representation can be changed into each other by calling re/setup_keyinfo_hash function.
Working:-
1. So when user specifies HASH_INDEX or key_length is > handler->max_key_length(), In mysql_prepare_create_table
One extra vfield is added (for each long unique key). And key_info->algorithm is set to HA_KEY_ALG_LONG_HASH.
2. In init_from_binary_frm_image values for hash_keypart is set (like fieldnr , field and flags)
3. In parse_vcol_defs, HASH_FIELD->vcol_info is created. Item_func_hash is used with list of Item_fields,
When Explicit length is given by user then Item_left is used to concatenate Item_field values.
4. In ha_write_row/ha_update_row check_duplicate_long_entry_key is called which will create the hash key from
table->record[0] and then call ha_index_read_map , if we found duplicated hash , we will compare the result
field by field.
2019-02-19 22:23:08 +01:00
|
|
|
--echo #test for concurrent insert of long unique in innodb
|
|
|
|
|
create table t1(a blob unique) engine= InnoDB;
|
|
|
|
|
show create table t1;
|
|
|
|
|
connect ('con1', localhost, root,,);
|
|
|
|
|
connect ('con2', localhost, root,,);
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
set innodb_lock_wait_timeout= 2;
|
|
|
|
|
set transaction isolation level READ UNCOMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('RUC');
|
|
|
|
|
--connection con2
|
|
|
|
|
set innodb_lock_wait_timeout= 2;
|
|
|
|
|
set transaction isolation level READ UNCOMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
--error ER_LOCK_WAIT_TIMEOUT
|
|
|
|
|
insert into t1 values ('RUC');
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
commit;
|
|
|
|
|
set transaction isolation level READ COMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('RC');
|
|
|
|
|
--connection con2
|
|
|
|
|
commit;
|
|
|
|
|
set transaction isolation level READ COMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
--error ER_LOCK_WAIT_TIMEOUT
|
|
|
|
|
insert into t1 values ('RC');
|
|
|
|
|
commit;
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
commit;
|
|
|
|
|
set transaction isolation level REPEATABLE READ;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('RR');
|
|
|
|
|
--connection con2
|
|
|
|
|
commit;
|
|
|
|
|
set transaction isolation level REPEATABLE READ;
|
|
|
|
|
start transaction;
|
|
|
|
|
--error ER_LOCK_WAIT_TIMEOUT
|
|
|
|
|
insert into t1 values ('RR');
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
commit;
|
|
|
|
|
set transaction isolation level SERIALIZABLE;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('S');
|
|
|
|
|
--connection con2
|
|
|
|
|
commit;
|
|
|
|
|
set transaction isolation level SERIALIZABLE;
|
|
|
|
|
start transaction;
|
|
|
|
|
--error ER_LOCK_WAIT_TIMEOUT
|
|
|
|
|
insert into t1 values ('S');
|
|
|
|
|
commit;
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
commit;
|
|
|
|
|
|
|
|
|
|
select * from t1;
|
|
|
|
|
drop table t1;
|
|
|
|
|
|
|
|
|
|
create table t1(a blob unique) engine=Innodb;
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
set transaction isolation level READ UNCOMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('RUC');
|
|
|
|
|
--connection con2
|
|
|
|
|
set transaction isolation level READ UNCOMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
--send insert into t1 values ('RUC');
|
|
|
|
|
--connection con1
|
|
|
|
|
rollback;
|
|
|
|
|
--connection con2
|
|
|
|
|
--reap
|
|
|
|
|
commit;
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
set transaction isolation level READ COMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('RC');
|
|
|
|
|
--connection con2
|
|
|
|
|
set transaction isolation level READ COMMITTED;
|
|
|
|
|
start transaction;
|
|
|
|
|
--send insert into t1 values ('RC');
|
|
|
|
|
--connection con1
|
|
|
|
|
rollback;
|
|
|
|
|
--connection con2
|
|
|
|
|
--reap
|
|
|
|
|
commit;
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
set transaction isolation level REPEATABLE READ;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('RR');
|
|
|
|
|
--connection con2
|
|
|
|
|
set transaction isolation level REPEATABLE READ;
|
|
|
|
|
start transaction;
|
|
|
|
|
--send insert into t1 values ('RR');
|
|
|
|
|
--connection con1
|
|
|
|
|
rollback;
|
|
|
|
|
--connection con2
|
|
|
|
|
--reap
|
|
|
|
|
commit;
|
|
|
|
|
|
|
|
|
|
--connection con1
|
|
|
|
|
set transaction isolation level SERIALIZABLE;
|
|
|
|
|
start transaction;
|
|
|
|
|
insert into t1 values('S');
|
|
|
|
|
--connection con2
|
|
|
|
|
set transaction isolation level SERIALIZABLE;
|
|
|
|
|
start transaction;
|
|
|
|
|
--send insert into t1 values ('S');
|
|
|
|
|
--connection con1
|
|
|
|
|
rollback;
|
|
|
|
|
--connection con2
|
|
|
|
|
--reap
|
|
|
|
|
commit;
|
|
|
|
|
|
|
|
|
|
connection default;
|
|
|
|
|
drop table t1;
|
|
|
|
|
disconnect con1;
|
|
|
|
|
disconnect con2;
|