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|
drop table if exists t1,t2;
set @my_connect_timeout =@@global.connect_timeout;
set @my_flush =@@global.flush;
set @my_key_buffer_size =@@global.key_buffer_size;
set @my_max_connect_errors =@@global.max_connect_errors;
set @my_max_heap_table_size =@@global.max_heap_table_size;
set @my_max_join_size =@@global.max_join_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_server_id =@@global.server_id;
set @my_slow_launch_time =@@global.slow_launch_time;
set @my_storage_engine =@@global.storage_engine;
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 NOT NULL, c_name VARCHAR(250), c_country VARCHAR(250), 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 2147483647
select * from information_schema.global_variables where variable_name like 'max_join_size';
VARIABLE_NAME VARIABLE_VALUE
MAX_JOIN_SIZE 2147483647
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 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 InnoDB
select * from information_schema.global_variables where variable_name like 'storage_engine';
VARIABLE_NAME VARIABLE_VALUE
STORAGE_ENGINE InnoDB
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 2000000
select * from information_schema.global_variables where variable_name like 'myisam_max_sort_file_size';
VARIABLE_NAME VARIABLE_VALUE
MYISAM_MAX_SORT_FILE_SIZE 2000000
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 2147483647
select * from information_schema.global_variables where variable_name like 'myisam_max_sort_file_size';
VARIABLE_NAME VARIABLE_VALUE
MYISAM_MAX_SORT_FILE_SIZE 2147483647
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
show variables like '%alloc%';
Variable_name Value
query_alloc_block_size 8192
query_prealloc_size 8192
range_alloc_block_size
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
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
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
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
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
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 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 GLOBAL storage_engine=DEFAULT;
ERROR 42000: Variable 'storage_engine' doesn't have a default value
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 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;
select @@autocommit;
@@autocommit
1
set bulk_insert_buffer_size=100;
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;
set global delay_key_write=1;
select @@delay_key_write;
@@delay_key_write
ON
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 max_allowed_packet=100;
Warnings:
Warning 1292 Truncated incorrect max_allowed_packet value: '100'
set global max_connect_errors=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_write_lock_count=100;
set global myisam_sort_buffer_size=100;
Warnings:
Warning 1292 Truncated incorrect sort_buffer_size value: '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 read_buffer_size=100;
Warnings:
Warning 1292 Truncated incorrect read_buffer_size value: '100'
set read_rnd_buffer_size=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 sql_big_selects=1;
set sql_buffer_result=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 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;
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 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 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;
set @@global.global.key_buffer_size= 1;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle 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 Drizzle 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 Drizzle 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 Drizzle 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 Drizzle server version for the right syntax to use near 'key_buffer_size' at line 1
create table t1 (
c1 int,
c2 int,
c3 int,
c4 int,
c5 bigint);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` int DEFAULT NULL,
`c2` int DEFAULT NULL,
`c3` int DEFAULT NULL,
`c4` int DEFAULT NULL,
`c5` bigint DEFAULT NULL
) ENGINE=MyISAM
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 DEFAULT NULL,
`c2` decimal(65,30) DEFAULT NULL,
`c3` text,
`c4` double DEFAULT NULL
) ENGINE=MyISAM
drop table t1;
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
SET GLOBAL table_open_cache=DEFAULT;
*** 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
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;
ERROR HY000: Unknown system variable 'character_set_system'
set global character_set_system = utf8;
ERROR HY000: Unknown system variable 'character_set_system'
set @@global.version_compile_os='234';
ERROR HY000: Variable 'version_compile_os' is a read only variable
set @@global.character_set_filesystem=utf8;
ERROR HY000: Unknown system variable 'character_set_filesystem'
set character_set_filesystem=utf8;
ERROR HY000: Unknown system variable 'character_set_filesystem'
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
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
show variables like 'sql_warnings';
Variable_name Value
sql_warnings OFF
set @@sql_notes = 1, @@sql_warnings = 1;
show variables like 'sql_notes';
Variable_name Value
sql_notes ON
show variables like 'sql_warnings';
Variable_name Value
sql_warnings ON
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 #
show variables like 'datadir';
Variable_name Value
datadir #
show variables like 'tmpdir';
Variable_name Value
tmpdir #
select @@"";
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle 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 Drizzle 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 Drizzle 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 connect_timeout =@my_connect_timeout;
set global flush =@my_flush;
set global flush_time =@my_flush_time;
ERROR HY000: Unknown system variable 'flush_time'
set global key_buffer_size =@my_key_buffer_size;
set global max_connect_errors =@my_max_connect_errors;
set global max_heap_table_size =@my_max_heap_table_size;
set global max_join_size =@my_max_join_size;
set global max_write_lock_count =default;
set global myisam_data_pointer_size =@my_myisam_data_pointer_size;
ERROR 42000: Incorrect argument type to variable '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 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;
ERROR HY000: Unknown system variable 'thread_cache_size'
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