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|
drop table if exists t1,t2;
set @my_binlog_cache_size =@@global.binlog_cache_size;
set @my_connect_timeout =@@global.connect_timeout;
set @my_delayed_insert_timeout =@@global.delayed_insert_timeout;
set @my_delayed_queue_size =@@global.delayed_queue_size;
set @my_flush =@@global.flush;
set @my_flush_time =@@global.flush_time;
set @my_key_buffer_size =@@global.key_buffer_size;
set @my_max_binlog_cache_size =@@global.max_binlog_cache_size;
set @my_max_binlog_size =@@global.max_binlog_size;
set @my_max_connect_errors =@@global.max_connect_errors;
set @my_max_connections =@@global.max_connections;
set @my_max_delayed_threads =@@global.max_delayed_threads;
set @my_max_heap_table_size =@@global.max_heap_table_size;
set @my_max_insert_delayed_threads=@@global.max_insert_delayed_threads;
set @my_max_join_size =@@global.max_join_size;
set @my_myisam_data_pointer_size =@@global.myisam_data_pointer_size;
set @my_net_buffer_length =@@global.net_buffer_length;
set @my_net_write_timeout =@@global.net_write_timeout;
set @my_net_read_timeout =@@global.net_read_timeout;
set @my_query_cache_limit =@@global.query_cache_limit;
set @my_query_cache_type =@@global.query_cache_type;
set @my_rpl_recovery_rank =@@global.rpl_recovery_rank;
set @my_server_id =@@global.server_id;
set @my_slow_launch_time =@@global.slow_launch_time;
set @my_storage_engine =@@global.storage_engine;
set @my_thread_cache_size =@@global.thread_cache_size;
set @`test`=1;
select @test, @`test`, @TEST, @`TEST`, @"teSt";
@test @`test` @TEST @`TEST` @"teSt"
1 1 1 1 1
set @TEST=2;
select @test, @`test`, @TEST, @`TEST`, @"teSt";
@test @`test` @TEST @`TEST` @"teSt"
2 2 2 2 2
set @"tEST"=3;
select @test, @`test`, @TEST, @`TEST`, @"teSt";
@test @`test` @TEST @`TEST` @"teSt"
3 3 3 3 3
set @`TeST`=4;
select @test, @`test`, @TEST, @`TEST`, @"teSt";
@test @`test` @TEST @`TEST` @"teSt"
4 4 4 4 4
select @`teST`:=5;
@`teST`:=5
5
select @test, @`test`, @TEST, @`TEST`, @"teSt";
@test @`test` @TEST @`TEST` @"teSt"
5 5 5 5 5
set @select=2,@t5=1.23456;
select @`select`,@not_used;
@`select` @not_used
2 NULL
set @test_int=10,@test_double=1e-10,@test_string="abcdeghi",@test_string2="abcdefghij",@select=NULL;
select @test_int,@test_double,@test_string,@test_string2,@select;
@test_int @test_double @test_string @test_string2 @select
10 0.0000000001 abcdeghi abcdefghij NULL
set @test_int="hello",@test_double="hello",@test_string="hello",@test_string2="hello";
select @test_int,@test_double,@test_string,@test_string2;
@test_int @test_double @test_string @test_string2
hello hello hello hello
set @test_int="hellohello",@test_double="hellohello",@test_string="hellohello",@test_string2="hellohello";
select @test_int,@test_double,@test_string,@test_string2;
@test_int @test_double @test_string @test_string2
hellohello hellohello hellohello hellohello
set @test_int=null,@test_double=null,@test_string=null,@test_string2=null;
select @test_int,@test_double,@test_string,@test_string2;
@test_int @test_double @test_string @test_string2
NULL NULL NULL NULL
select @t1:=(@t2:=1)+@t3:=4,@t1,@t2,@t3;
@t1:=(@t2:=1)+@t3:=4 @t1 @t2 @t3
5 5 1 4
explain extended select @t1:=(@t2:=1)+@t3:=4,@t1,@t2,@t3;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select (@t1:=((@t2:=1) + (@t3:=4))) AS `@t1:=(@t2:=1)+@t3:=4`,(@t1) AS `@t1`,(@t2) AS `@t2`,(@t3) AS `@t3`
select @t5;
@t5
1.23456
CREATE TABLE t1 (c_id INT(4) NOT NULL, c_name CHAR(20), c_country CHAR(3), PRIMARY KEY(c_id));
INSERT INTO t1 VALUES (1,'Bozo','USA'),(2,'Ronald','USA'),(3,'Kinko','IRE'),(4,'Mr. Floppy','GB');
SELECT @min_cid:=min(c_id), @max_cid:=max(c_id) from t1;
@min_cid:=min(c_id) @max_cid:=max(c_id)
1 4
SELECT * FROM t1 WHERE c_id=@min_cid OR c_id=@max_cid;
c_id c_name c_country
1 Bozo USA
4 Mr. Floppy GB
SELECT * FROM t1 WHERE c_id=@min_cid OR c_id=@max_cid OR c_id=666;
c_id c_name c_country
1 Bozo USA
4 Mr. Floppy GB
ALTER TABLE t1 DROP PRIMARY KEY;
select * from t1 where c_id=@min_cid OR c_id=@max_cid;
c_id c_name c_country
1 Bozo USA
4 Mr. Floppy GB
drop table t1;
set GLOBAL max_join_size=10;
set max_join_size=100;
show variables like 'max_join_size';
Variable_name Value
max_join_size 100
select * from information_schema.session_variables where variable_name like 'max_join_size';
VARIABLE_NAME VARIABLE_VALUE
MAX_JOIN_SIZE 100
show global variables like 'max_join_size';
Variable_name Value
max_join_size 10
select * from information_schema.global_variables where variable_name like 'max_join_size';
VARIABLE_NAME VARIABLE_VALUE
MAX_JOIN_SIZE 10
set GLOBAL max_join_size=2000;
show global variables like 'max_join_size';
Variable_name Value
max_join_size 2000
select * from information_schema.global_variables where variable_name like 'max_join_size';
VARIABLE_NAME VARIABLE_VALUE
MAX_JOIN_SIZE 2000
set max_join_size=DEFAULT;
show variables like 'max_join_size';
Variable_name Value
max_join_size 2000
select * from information_schema.session_variables where variable_name like 'max_join_size';
VARIABLE_NAME VARIABLE_VALUE
MAX_JOIN_SIZE 2000
set GLOBAL max_join_size=DEFAULT;
show global variables like 'max_join_size';
Variable_name Value
max_join_size HA_POS_ERROR
select * from information_schema.global_variables where variable_name like 'max_join_size';
VARIABLE_NAME VARIABLE_VALUE
MAX_JOIN_SIZE HA_POS_ERROR
set @@max_join_size=1000, @@global.max_join_size=2000;
select @@local.max_join_size, @@global.max_join_size;
@@local.max_join_size @@global.max_join_size
1000 2000
select @@identity, length(@@version)>0;
@@identity length(@@version)>0
0 1
select @@VERSION=version();
@@VERSION=version()
1
select last_insert_id(345);
last_insert_id(345)
345
explain extended select last_insert_id(345);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select last_insert_id(345) AS `last_insert_id(345)`
select @@IDENTITY,last_insert_id(), @@identity;
@@IDENTITY last_insert_id() @@identity
345 345 345
explain extended select @@IDENTITY,last_insert_id(), @@identity;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select 345 AS `@@IDENTITY`,last_insert_id() AS `last_insert_id()`,345 AS `@@identity`
set big_tables=OFF, big_tables=ON, big_tables=0, big_tables=1, big_tables="OFF", big_tables="ON";
set global concurrent_insert=2;
show variables like 'concurrent_insert';
Variable_name Value
concurrent_insert 2
select * from information_schema.session_variables where variable_name like 'concurrent_insert';
VARIABLE_NAME VARIABLE_VALUE
CONCURRENT_INSERT 2
set global concurrent_insert=1;
show variables like 'concurrent_insert';
Variable_name Value
concurrent_insert 1
select * from information_schema.session_variables where variable_name like 'concurrent_insert';
VARIABLE_NAME VARIABLE_VALUE
CONCURRENT_INSERT 1
set global concurrent_insert=0;
show variables like 'concurrent_insert';
Variable_name Value
concurrent_insert 0
select * from information_schema.session_variables where variable_name like 'concurrent_insert';
VARIABLE_NAME VARIABLE_VALUE
CONCURRENT_INSERT 0
set global concurrent_insert=DEFAULT;
select @@concurrent_insert;
@@concurrent_insert
1
set global timed_mutexes=ON;
show variables like 'timed_mutexes';
Variable_name Value
timed_mutexes ON
select * from information_schema.session_variables where variable_name like 'timed_mutexes';
VARIABLE_NAME VARIABLE_VALUE
TIMED_MUTEXES ON
set global timed_mutexes=0;
show variables like 'timed_mutexes';
Variable_name Value
timed_mutexes OFF
select * from information_schema.session_variables where variable_name like 'timed_mutexes';
VARIABLE_NAME VARIABLE_VALUE
TIMED_MUTEXES OFF
set storage_engine=MYISAM, storage_engine="HEAP";
show local variables like 'storage_engine';
Variable_name Value
storage_engine MEMORY
select * from information_schema.session_variables where variable_name like 'storage_engine';
VARIABLE_NAME VARIABLE_VALUE
STORAGE_ENGINE MEMORY
show global variables like 'storage_engine';
Variable_name Value
storage_engine MyISAM
select * from information_schema.global_variables where variable_name like 'storage_engine';
VARIABLE_NAME VARIABLE_VALUE
STORAGE_ENGINE MyISAM
set GLOBAL query_cache_size=100000;
set GLOBAL myisam_max_sort_file_size=2000000;
show global variables like 'myisam_max_sort_file_size';
Variable_name Value
myisam_max_sort_file_size 1048576
select * from information_schema.global_variables where variable_name like 'myisam_max_sort_file_size';
VARIABLE_NAME VARIABLE_VALUE
MYISAM_MAX_SORT_FILE_SIZE 1048576
set GLOBAL myisam_max_sort_file_size=default;
show global variables like 'myisam_max_sort_file_size';
Variable_name Value
myisam_max_sort_file_size FILE_SIZE
select * from information_schema.global_variables where variable_name like 'myisam_max_sort_file_size';
VARIABLE_NAME VARIABLE_VALUE
MYISAM_MAX_SORT_FILE_SIZE FILE_SIZE
set global net_retry_count=10, session net_retry_count=10;
set global net_buffer_length=1024, net_write_timeout=200, net_read_timeout=300;
set session net_buffer_length=2048, net_write_timeout=500, net_read_timeout=600;
show global variables like 'net_%';
Variable_name Value
net_buffer_length 1024
net_read_timeout 300
net_retry_count 10
net_write_timeout 200
select * from information_schema.global_variables where variable_name like 'net_%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
NET_BUFFER_LENGTH 1024
NET_READ_TIMEOUT 300
NET_RETRY_COUNT 10
NET_WRITE_TIMEOUT 200
show session variables like 'net_%';
Variable_name Value
net_buffer_length 2048
net_read_timeout 600
net_retry_count 10
net_write_timeout 500
select * from information_schema.session_variables where variable_name like 'net_%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
NET_BUFFER_LENGTH 2048
NET_READ_TIMEOUT 600
NET_RETRY_COUNT 10
NET_WRITE_TIMEOUT 500
set session net_buffer_length=8000, global net_read_timeout=900, net_write_timeout=1000;
show global variables like 'net_%';
Variable_name Value
net_buffer_length 1024
net_read_timeout 900
net_retry_count 10
net_write_timeout 1000
select * from information_schema.global_variables where variable_name like 'net_%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
NET_BUFFER_LENGTH 1024
NET_READ_TIMEOUT 900
NET_RETRY_COUNT 10
NET_WRITE_TIMEOUT 1000
show session variables like 'net_%';
Variable_name Value
net_buffer_length 7168
net_read_timeout 600
net_retry_count 10
net_write_timeout 500
select * from information_schema.session_variables where variable_name like 'net_%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
NET_BUFFER_LENGTH 7168
NET_READ_TIMEOUT 600
NET_RETRY_COUNT 10
NET_WRITE_TIMEOUT 500
set net_buffer_length=1;
Warnings:
Warning 1292 Truncated incorrect net_buffer_length value: '1'
show variables like 'net_buffer_length';
Variable_name Value
net_buffer_length 1024
select * from information_schema.session_variables where variable_name like 'net_buffer_length';
VARIABLE_NAME VARIABLE_VALUE
NET_BUFFER_LENGTH 1024
set net_buffer_length=2000000000;
Warnings:
Warning 1292 Truncated incorrect net_buffer_length value: '2000000000'
show variables like 'net_buffer_length';
Variable_name Value
net_buffer_length 1048576
select * from information_schema.session_variables where variable_name like 'net_buffer_length';
VARIABLE_NAME VARIABLE_VALUE
NET_BUFFER_LENGTH 1048576
set character set cp1251_koi8;
show variables like "character_set_client";
Variable_name Value
character_set_client cp1251
select * from information_schema.session_variables where variable_name like 'character_set_client';
VARIABLE_NAME VARIABLE_VALUE
CHARACTER_SET_CLIENT cp1251
select @@timestamp>0;
@@timestamp>0
1
set @@rand_seed1=10000000,@@rand_seed2=1000000;
select ROUND(RAND(),5);
ROUND(RAND(),5)
0.02887
show variables like '%alloc%';
Variable_name Value
query_alloc_block_size 8192
query_prealloc_size 8192
range_alloc_block_size 4096
transaction_alloc_block_size 8192
transaction_prealloc_size 4096
select * from information_schema.session_variables where variable_name like '%alloc%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
QUERY_ALLOC_BLOCK_SIZE 8192
QUERY_PREALLOC_SIZE 8192
RANGE_ALLOC_BLOCK_SIZE 4096
TRANSACTION_ALLOC_BLOCK_SIZE 8192
TRANSACTION_PREALLOC_SIZE 4096
set @@range_alloc_block_size=1024*16;
set @@query_alloc_block_size=1024*17+2;
set @@query_prealloc_size=1024*18;
set @@transaction_alloc_block_size=1024*20-1;
set @@transaction_prealloc_size=1024*21-1;
select @@query_alloc_block_size;
@@query_alloc_block_size
17408
show variables like '%alloc%';
Variable_name Value
query_alloc_block_size 17408
query_prealloc_size 18432
range_alloc_block_size 16384
transaction_alloc_block_size 19456
transaction_prealloc_size 20480
select * from information_schema.session_variables where variable_name like '%alloc%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
QUERY_ALLOC_BLOCK_SIZE 17408
QUERY_PREALLOC_SIZE 18432
RANGE_ALLOC_BLOCK_SIZE 16384
TRANSACTION_ALLOC_BLOCK_SIZE 19456
TRANSACTION_PREALLOC_SIZE 20480
set @@range_alloc_block_size=default;
set @@query_alloc_block_size=default, @@query_prealloc_size=default;
set transaction_alloc_block_size=default, @@transaction_prealloc_size=default;
show variables like '%alloc%';
Variable_name Value
query_alloc_block_size 8192
query_prealloc_size 8192
range_alloc_block_size 4096
transaction_alloc_block_size 8192
transaction_prealloc_size 4096
select * from information_schema.session_variables where variable_name like '%alloc%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
QUERY_ALLOC_BLOCK_SIZE 8192
QUERY_PREALLOC_SIZE 8192
RANGE_ALLOC_BLOCK_SIZE 4096
TRANSACTION_ALLOC_BLOCK_SIZE 8192
TRANSACTION_PREALLOC_SIZE 4096
SELECT @@version LIKE 'non-existent';
@@version LIKE 'non-existent'
0
SELECT @@version_compile_os LIKE 'non-existent';
@@version_compile_os LIKE 'non-existent'
0
set big_tables=OFFF;
ERROR 42000: Variable 'big_tables' can't be set to the value of 'OFFF'
set big_tables="OFFF";
ERROR 42000: Variable 'big_tables' can't be set to the value of 'OFFF'
set unknown_variable=1;
ERROR HY000: Unknown system variable 'unknown_variable'
set max_join_size="hello";
ERROR 42000: Incorrect argument type to variable 'max_join_size'
set storage_engine=UNKNOWN_TABLE_TYPE;
ERROR 42000: Unknown table engine 'UNKNOWN_TABLE_TYPE'
set SESSION query_cache_size=10000;
ERROR HY000: Variable 'query_cache_size' is a GLOBAL variable and should be set with SET GLOBAL
set GLOBAL storage_engine=DEFAULT;
ERROR 42000: Variable 'storage_engine' doesn't have a default value
set character_set_client=UNKNOWN_CHARACTER_SET;
ERROR 42000: Unknown character set: 'UNKNOWN_CHARACTER_SET'
set collation_connection=UNKNOWN_COLLATION;
ERROR HY000: Unknown collation: 'UNKNOWN_COLLATION'
set character_set_client=NULL;
ERROR 42000: Variable 'character_set_client' can't be set to the value of 'NULL'
set collation_connection=NULL;
ERROR 42000: Variable 'collation_connection' can't be set to the value of 'NULL'
set global autocommit=1;
ERROR HY000: Variable 'autocommit' is a SESSION variable and can't be used with SET GLOBAL
select @@global.timestamp;
ERROR HY000: Variable 'timestamp' is a SESSION variable
set @@version='';
ERROR HY000: Variable 'version' is a read only variable
set @@concurrent_insert=1;
ERROR HY000: Variable 'concurrent_insert' is a GLOBAL variable and should be set with SET GLOBAL
set @@global.sql_auto_is_null=1;
ERROR HY000: Variable 'sql_auto_is_null' is a SESSION variable and can't be used with SET GLOBAL
select @@global.sql_auto_is_null;
ERROR HY000: Variable 'sql_auto_is_null' is a SESSION variable
set myisam_max_sort_file_size=100;
ERROR HY000: Variable 'myisam_max_sort_file_size' is a GLOBAL variable and should be set with SET GLOBAL
set @@SQL_WARNINGS=NULL;
ERROR 42000: Variable 'sql_warnings' can't be set to the value of 'NULL'
set autocommit=1;
set big_tables=1;
select @@autocommit, @@big_tables;
@@autocommit @@big_tables
1 1
set global binlog_cache_size=100;
Warnings:
Warning 1292 Truncated incorrect binlog_cache_size value: '100'
set bulk_insert_buffer_size=100;
set character set cp1251_koi8;
set character set default;
set @@global.concurrent_insert=1;
set global connect_timeout=100;
select @@delay_key_write;
@@delay_key_write
ON
set global delay_key_write="OFF";
select @@delay_key_write;
@@delay_key_write
OFF
set global delay_key_write=ALL;
select @@delay_key_write;
@@delay_key_write
ALL
set global delay_key_write=1;
select @@delay_key_write;
@@delay_key_write
ON
set global delayed_insert_limit=100;
set global delayed_insert_timeout=100;
set global delayed_queue_size=100;
set global flush=1;
set global flush_time=100;
set insert_id=1;
set interactive_timeout=100;
set join_buffer_size=100;
Warnings:
Warning 1292 Truncated incorrect join_buffer_size value: '100'
set last_insert_id=1;
set global local_infile=1;
set long_query_time=0.000001;
select @@long_query_time;
@@long_query_time
0.000001
set long_query_time=100.000001;
select @@long_query_time;
@@long_query_time
100.000001
set low_priority_updates=1;
set max_allowed_packet=100;
Warnings:
Warning 1292 Truncated incorrect max_allowed_packet value: '100'
set global max_binlog_cache_size=100;
Warnings:
Warning 1292 Truncated incorrect max_binlog_cache_size value: '100'
set global max_binlog_size=100;
Warnings:
Warning 1292 Truncated incorrect max_binlog_size value: '100'
set global max_connect_errors=100;
set global max_connections=100;
set global max_delayed_threads=100;
set max_heap_table_size=100;
Warnings:
Warning 1292 Truncated incorrect max_heap_table_size value: '100'
set max_join_size=100;
set max_sort_length=100;
set max_tmp_tables=100;
set global max_user_connections=100;
select @@max_user_connections;
@@max_user_connections
100
set global max_write_lock_count=100;
set myisam_sort_buffer_size=100;
set net_buffer_length=100;
Warnings:
Warning 1292 Truncated incorrect net_buffer_length value: '100'
set net_read_timeout=100;
set net_write_timeout=100;
set global query_cache_limit=100;
set global query_cache_size=100;
set global query_cache_type=demand;
set read_buffer_size=100;
Warnings:
Warning 1292 Truncated incorrect read_buffer_size value: '100'
set read_rnd_buffer_size=100;
set global rpl_recovery_rank=100;
set global server_id=100;
set global slow_launch_time=100;
set sort_buffer_size=100;
Warnings:
Warning 1292 Truncated incorrect sort_buffer_size value: '100'
set @@max_sp_recursion_depth=10;
select @@max_sp_recursion_depth;
@@max_sp_recursion_depth
10
set @@max_sp_recursion_depth=0;
select @@max_sp_recursion_depth;
@@max_sp_recursion_depth
0
set sql_auto_is_null=1;
select @@sql_auto_is_null;
@@sql_auto_is_null
1
set @@sql_auto_is_null=0;
select @@sql_auto_is_null;
@@sql_auto_is_null
0
set sql_big_selects=1;
set sql_big_tables=1;
set sql_buffer_result=1;
set sql_log_bin=1;
set sql_log_off=1;
set sql_log_update=1;
Warnings:
Note 1315 The update log is deprecated and replaced by the binary log; SET SQL_LOG_UPDATE has been ignored
set sql_low_priority_updates=1;
set sql_max_join_size=200;
select @@sql_max_join_size,@@max_join_size;
@@sql_max_join_size @@max_join_size
200 200
set sql_quote_show_create=1;
set sql_safe_updates=1;
set sql_select_limit=1;
set sql_select_limit=default;
set sql_warnings=1;
set global table_open_cache=100;
set storage_engine=myisam;
set global thread_cache_size=100;
set timestamp=1, timestamp=default;
set tmp_table_size=100;
Warnings:
Warning 1292 Truncated incorrect tmp_table_size value: '100'
set tx_isolation="READ-COMMITTED";
set wait_timeout=100;
set log_warnings=1;
set global log_warnings=1;
select @@session.insert_id;
@@session.insert_id
1
set @save_insert_id=@@session.insert_id;
set session insert_id=20;
select @@session.insert_id;
@@session.insert_id
20
set session last_insert_id=100;
select @@session.insert_id;
@@session.insert_id
20
select @@session.last_insert_id;
@@session.last_insert_id
100
select @@session.insert_id;
@@session.insert_id
20
set @@session.insert_id=@save_insert_id;
select @@session.insert_id;
@@session.insert_id
1
create table t1 (a int not null auto_increment, primary key(a));
create table t2 (a int not null auto_increment, primary key(a));
insert into t1 values(null),(null),(null);
insert into t2 values(null),(null),(null);
set global key_buffer_size=100000;
select @@key_buffer_size;
@@key_buffer_size
98304
select * from t1 where a=2;
a
2
select * from t2 where a=3;
a
3
check table t1,t2;
Table Op Msg_type Msg_text
test.t1 check status OK
test.t2 check status OK
select max(a) +1, max(a) +2 into @xx,@yy from t1;
drop table t1,t2;
select @@xxxxxxxxxx;
ERROR HY000: Unknown system variable 'xxxxxxxxxx'
select 1;
1
1
select @@session.key_buffer_size;
ERROR HY000: Variable 'key_buffer_size' is a GLOBAL variable
set ft_boolean_syntax = @@init_connect;
ERROR HY000: Variable 'ft_boolean_syntax' is a GLOBAL variable and should be set with SET GLOBAL
set global ft_boolean_syntax = @@init_connect;
ERROR 42000: Variable 'ft_boolean_syntax' can't be set to the value of ''
set init_connect = NULL;
ERROR HY000: Variable 'init_connect' is a GLOBAL variable and should be set with SET GLOBAL
set global init_connect = NULL;
set ft_boolean_syntax = @@init_connect;
ERROR HY000: Variable 'ft_boolean_syntax' is a GLOBAL variable and should be set with SET GLOBAL
set global ft_boolean_syntax = @@init_connect;
ERROR 42000: Variable 'ft_boolean_syntax' can't be set to the value of ''
set global myisam_max_sort_file_size=4294967296;
show global variables like 'myisam_max_sort_file_size';
Variable_name Value
myisam_max_sort_file_size MAX_FILE_SIZE
select * from information_schema.global_variables where variable_name like 'myisam_max_sort_file_size';
VARIABLE_NAME VARIABLE_VALUE
MYISAM_MAX_SORT_FILE_SIZE MAX_FILE_SIZE
set global myisam_max_sort_file_size=default;
select @@global.max_user_connections,@@local.max_join_size;
@@global.max_user_connections @@local.max_join_size
100 200
set @svc=@@global.max_user_connections, @svj=@@local.max_join_size;
select @@global.max_user_connections,@@local.max_join_size;
@@global.max_user_connections @@local.max_join_size
100 200
set @@global.max_user_connections=111,@@local.max_join_size=222;
select @@global.max_user_connections,@@local.max_join_size;
@@global.max_user_connections @@local.max_join_size
111 222
set @@global.max_user_connections=@@local.max_join_size,@@local.max_join_size=@@global.max_user_connections;
select @@global.max_user_connections,@@local.max_join_size;
@@global.max_user_connections @@local.max_join_size
222 111
set @@global.max_user_connections=@svc, @@local.max_join_size=@svj;
select @@global.max_user_connections,@@local.max_join_size;
@@global.max_user_connections @@local.max_join_size
100 200
set @a=1, @b=2;
set @a=@b, @b=@a;
select @a, @b;
@a @b
2 1
set @@global.global.key_buffer_size= 1;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'key_buffer_size= 1' at line 1
set GLOBAL global.key_buffer_size= 1;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'key_buffer_size= 1' at line 1
SELECT @@global.global.key_buffer_size;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'key_buffer_size' at line 1
SELECT @@global.session.key_buffer_size;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'key_buffer_size' at line 1
SELECT @@global.local.key_buffer_size;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'key_buffer_size' at line 1
set @tstlw = @@log_warnings;
show global variables like 'log_warnings';
Variable_name Value
log_warnings 1
select * from information_schema.global_variables where variable_name like 'log_warnings';
VARIABLE_NAME VARIABLE_VALUE
LOG_WARNINGS 1
set global log_warnings = 0;
show global variables like 'log_warnings';
Variable_name Value
log_warnings 0
select * from information_schema.global_variables where variable_name like 'log_warnings';
VARIABLE_NAME VARIABLE_VALUE
LOG_WARNINGS 0
set global log_warnings = 42;
show global variables like 'log_warnings';
Variable_name Value
log_warnings 42
select * from information_schema.global_variables where variable_name like 'log_warnings';
VARIABLE_NAME VARIABLE_VALUE
LOG_WARNINGS 42
set global log_warnings = @tstlw;
show global variables like 'log_warnings';
Variable_name Value
log_warnings 1
select * from information_schema.global_variables where variable_name like 'log_warnings';
VARIABLE_NAME VARIABLE_VALUE
LOG_WARNINGS 1
create table t1 (
c1 tinyint,
c2 smallint,
c3 mediumint,
c4 int,
c5 bigint);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` tinyint(4) DEFAULT NULL,
`c2` smallint(6) DEFAULT NULL,
`c3` mediumint(9) DEFAULT NULL,
`c4` int(11) DEFAULT NULL,
`c5` bigint(20) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
set @arg00= 8, @arg01= 8.8, @arg02= 'a string', @arg03= 0.2e0;
create table t1 as select @arg00 as c1, @arg01 as c2, @arg02 as c3, @arg03 as c4;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` bigint(20) DEFAULT NULL,
`c2` decimal(65,30) DEFAULT NULL,
`c3` longtext,
`c4` double DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
SET GLOBAL MYISAM_DATA_POINTER_SIZE= 7;
SHOW VARIABLES LIKE 'MYISAM_DATA_POINTER_SIZE';
Variable_name Value
myisam_data_pointer_size 7
SELECT * FROM INFORMATION_SCHEMA.SESSION_VARIABLES WHERE VARIABLE_NAME LIKE 'MYISAM_DATA_POINTER_SIZE';
VARIABLE_NAME VARIABLE_VALUE
MYISAM_DATA_POINTER_SIZE 7
SET GLOBAL table_open_cache=-1;
Warnings:
Warning 1292 Truncated incorrect table_open_cache value: '0'
SHOW VARIABLES LIKE 'table_open_cache';
Variable_name Value
table_open_cache 1
SELECT * FROM INFORMATION_SCHEMA.SESSION_VARIABLES WHERE VARIABLE_NAME LIKE 'table_open_cache';
VARIABLE_NAME VARIABLE_VALUE
TABLE_OPEN_CACHE 1
SET GLOBAL table_open_cache=DEFAULT;
set character_set_results=NULL;
select ifnull(@@character_set_results,"really null");
ifnull(@@character_set_results,"really null")
really null
set names latin1;
select @@have_innodb;
@@have_innodb
#
*** Various tests with LC_TIME_NAMES
*** LC_TIME_NAMES: testing case insensitivity
set @@lc_time_names='ru_ru';
select @@lc_time_names;
@@lc_time_names
ru_RU
*** LC_TIME_NAMES: testing with a user variable
set @lc='JA_JP';
set @@lc_time_names=@lc;
select @@lc_time_names;
@@lc_time_names
ja_JP
*** LC_TIME_NAMES: testing with string expressions
set lc_time_names=concat('de','_','DE');
select @@lc_time_names;
@@lc_time_names
de_DE
set lc_time_names=concat('de','+','DE');
ERROR HY000: Unknown locale: 'de+DE'
select @@lc_time_names;
@@lc_time_names
de_DE
LC_TIME_NAMES: testing with numeric expressions
set @@lc_time_names=1+2;
select @@lc_time_names;
@@lc_time_names
sv_SE
set @@lc_time_names=1/0;
ERROR 42000: Incorrect argument type to variable 'lc_time_names'
select @@lc_time_names;
@@lc_time_names
sv_SE
set lc_time_names=en_US;
LC_TIME_NAMES: testing NULL and a negative number:
set lc_time_names=NULL;
ERROR 42000: Variable 'lc_time_names' can't be set to the value of 'NULL'
set lc_time_names=-1;
ERROR HY000: Unknown locale: '-1'
select @@lc_time_names;
@@lc_time_names
en_US
LC_TIME_NAMES: testing locale with the last ID:
set lc_time_names=108;
select @@lc_time_names;
@@lc_time_names
zh_HK
LC_TIME_NAMES: testing a number beyond the valid ID range:
set lc_time_names=109;
ERROR HY000: Unknown locale: '109'
select @@lc_time_names;
@@lc_time_names
zh_HK
LC_TIME_NAMES: testing that 0 is en_US:
set lc_time_names=0;
select @@lc_time_names;
@@lc_time_names
en_US
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
en_US en_US
set @@global.lc_time_names=fr_FR;
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
fr_FR en_US
New connection
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
fr_FR fr_FR
set @@lc_time_names=ru_RU;
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
fr_FR ru_RU
Returnung to default connection
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
fr_FR en_US
set lc_time_names=default;
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
fr_FR fr_FR
set @@global.lc_time_names=default;
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
en_US fr_FR
set @@lc_time_names=default;
select @@global.lc_time_names, @@lc_time_names;
@@global.lc_time_names @@lc_time_names
en_US en_US
set @test = @@query_prealloc_size;
set @@query_prealloc_size = @test;
select @@query_prealloc_size = @test;
@@query_prealloc_size = @test
1
set global sql_mode=repeat('a',80);
ERROR 42000: Variable 'sql_mode' can't be set to the value of 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'
End of 4.1 tests
create table t1 (a int);
select a into @x from t1;
Warnings:
Warning 1329 No data - zero rows fetched, selected, or processed
show warnings;
Level Code Message
Warning 1329 No data - zero rows fetched, selected, or processed
drop table t1;
set @@warning_count=1;
ERROR HY000: Variable 'warning_count' is a read only variable
set @@global.error_count=1;
ERROR HY000: Variable 'error_count' is a read only variable
set @@max_heap_table_size= 4294967296;
select @@max_heap_table_size > 0;
@@max_heap_table_size > 0
1
set global max_heap_table_size= 4294967296;
select @@max_heap_table_size > 0;
@@max_heap_table_size > 0
1
set @@max_heap_table_size= 4294967296;
select @@max_heap_table_size > 0;
@@max_heap_table_size > 0
1
select @@character_set_system;
@@character_set_system
utf8
set global character_set_system = latin1;
ERROR HY000: Variable 'character_set_system' is a read only variable
set @@global.version_compile_os='234';
ERROR HY000: Variable 'version_compile_os' is a read only variable
set character_set_filesystem=latin1;
select @@character_set_filesystem;
@@character_set_filesystem
latin1
set @@global.character_set_filesystem=latin2;
set character_set_filesystem=latin1;
select @@character_set_filesystem;
@@character_set_filesystem
latin1
set @@global.character_set_filesystem=latin2;
set character_set_filesystem=default;
select @@character_set_filesystem;
@@character_set_filesystem
latin2
set @@global.character_set_filesystem=default;
select @@global.character_set_filesystem;
@@global.character_set_filesystem
binary
set @old_sql_big_selects = @@sql_big_selects;
set @@sql_big_selects = 1;
show variables like 'sql_big_selects';
Variable_name Value
sql_big_selects ON
select * from information_schema.session_variables where variable_name like 'sql_big_selects';
VARIABLE_NAME VARIABLE_VALUE
SQL_BIG_SELECTS ON
set @@sql_big_selects = @old_sql_big_selects;
set @@sql_notes = 0, @@sql_warnings = 0;
show variables like 'sql_notes';
Variable_name Value
sql_notes OFF
select * from information_schema.session_variables where variable_name like 'sql_notes';
VARIABLE_NAME VARIABLE_VALUE
SQL_NOTES OFF
show variables like 'sql_warnings';
Variable_name Value
sql_warnings OFF
select * from information_schema.session_variables where variable_name like 'sql_warnings';
VARIABLE_NAME VARIABLE_VALUE
SQL_WARNINGS OFF
set @@sql_notes = 1, @@sql_warnings = 1;
show variables like 'sql_notes';
Variable_name Value
sql_notes ON
select * from information_schema.session_variables where variable_name like 'sql_notes';
VARIABLE_NAME VARIABLE_VALUE
SQL_NOTES ON
show variables like 'sql_warnings';
Variable_name Value
sql_warnings ON
select * from information_schema.session_variables where variable_name like 'sql_warnings';
VARIABLE_NAME VARIABLE_VALUE
SQL_WARNINGS ON
select @@system_time_zone;
@@system_time_zone
#
select @@version, @@version_comment, @@version_compile_machine,
@@version_compile_os;
@@version @@version_comment @@version_compile_machine @@version_compile_os
# # # #
select @@basedir, @@datadir, @@tmpdir;
@@basedir @@datadir @@tmpdir
# # #
show variables like 'basedir';
Variable_name Value
basedir #
select * from information_schema.session_variables where variable_name like 'basedir';
VARIABLE_NAME VARIABLE_VALUE
BASEDIR #
show variables like 'datadir';
Variable_name Value
datadir #
select * from information_schema.session_variables where variable_name like 'datadir';
VARIABLE_NAME VARIABLE_VALUE
DATADIR #
show variables like 'tmpdir';
Variable_name Value
tmpdir #
select * from information_schema.session_variables where variable_name like 'tmpdir';
VARIABLE_NAME VARIABLE_VALUE
TMPDIR #
select @@ssl_ca, @@ssl_capath, @@ssl_cert, @@ssl_cipher, @@ssl_key;
@@ssl_ca @@ssl_capath @@ssl_cert @@ssl_cipher @@ssl_key
# # # # #
show variables like 'ssl%';
Variable_name Value
ssl_ca #
ssl_capath #
ssl_cert #
ssl_cipher #
ssl_key #
select * from information_schema.session_variables where variable_name like 'ssl%' order by 1;
VARIABLE_NAME VARIABLE_VALUE
SSL_CA #
SSL_CAPATH #
SSL_CERT #
SSL_CIPHER #
SSL_KEY #
select @@log_queries_not_using_indexes;
@@log_queries_not_using_indexes
0
show variables like 'log_queries_not_using_indexes';
Variable_name Value
log_queries_not_using_indexes OFF
select * from information_schema.session_variables where variable_name like 'log_queries_not_using_indexes';
VARIABLE_NAME VARIABLE_VALUE
LOG_QUERIES_NOT_USING_INDEXES OFF
select @@"";
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '""' at line 1
select @@&;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '&' at line 1
select @@@;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '@' at line 1
select @@hostname;
@@hostname
#
set @@hostname= "anothername";
ERROR HY000: Variable 'hostname' is a read only variable
show variables like 'hostname';
Variable_name Value
hostname #
End of 5.0 tests
set global binlog_cache_size =@my_binlog_cache_size;
set global connect_timeout =@my_connect_timeout;
set global delayed_insert_timeout =@my_delayed_insert_timeout;
set global delayed_queue_size =@my_delayed_queue_size;
set global flush =@my_flush;
set global flush_time =@my_flush_time;
set global key_buffer_size =@my_key_buffer_size;
set global max_binlog_cache_size =default;
set global max_binlog_size =@my_max_binlog_size;
set global max_connect_errors =@my_max_connect_errors;
set global max_connections =@my_max_connections;
set global max_delayed_threads =@my_max_delayed_threads;
set global max_heap_table_size =@my_max_heap_table_size;
set global max_insert_delayed_threads=@my_max_insert_delayed_threads;
set global max_join_size =@my_max_join_size;
set global max_user_connections =default;
set global max_write_lock_count =default;
set global myisam_data_pointer_size =@my_myisam_data_pointer_size;
set global net_buffer_length =@my_net_buffer_length;
set global net_write_timeout =@my_net_write_timeout;
set global net_read_timeout =@my_net_read_timeout;
set global query_cache_limit =@my_query_cache_limit;
set global query_cache_type =@my_query_cache_type;
set global rpl_recovery_rank =@my_rpl_recovery_rank;
set global server_id =@my_server_id;
set global slow_launch_time =@my_slow_launch_time;
set global storage_engine =@my_storage_engine;
set global thread_cache_size =@my_thread_cache_size;
show global variables where Variable_name='table_definition_cache' or
Variable_name='table_lock_wait_timeout';
Variable_name Value
table_definition_cache #
table_lock_wait_timeout #
# --
# -- Bug#34820: log_output can be set to illegal value.
# --
SET GLOBAL log_output = '';
ERROR 42000: Variable 'log_output' can't be set to the value of ''
SET GLOBAL log_output = 0;
ERROR 42000: Variable 'log_output' can't be set to the value of '0'
# -- End of Bug#34820.
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