SET @start_value = @@global.flush;
SELECT @start_value;
@start_value
0
'#--------------------FN_DYNVARS_030_01------------------------#'
SET @@global.flush = ON;
SET @@global.flush = DEFAULT;
SELECT @@global.flush;
@@global.flush
0
'#---------------------FN_DYNVARS_030_02-------------------------#'
SET @@global.flush = @start_value;
SELECT @@global.flush;
@@global.flush
0
'#--------------------FN_DYNVARS_030_03------------------------#'
SET @@global.flush = ON;
SELECT @@global.flush;
@@global.flush
1
SET @@global.flush = OFF;
SELECT @@global.flush;
@@global.flush
0
SET @@global.flush = 0;
SELECT @@global.flush;
@@global.flush
0
SET @@global.flush = 1;
SELECT @@global.flush;
@@global.flush
1
'#--------------------FN_DYNVARS_030_04-------------------------#'
SET @@global.flush = 2;
ERROR 42000: Variable 'flush' can't be set to the value of '2'
SET @@global.flush = -1;
ERROR 42000: Variable 'flush' can't be set to the value of '-1'
SET @@global.flush = TRUEF;
ERROR 42000: Variable 'flush' can't be set to the value of 'TRUEF'
SET @@global.flush = TRUE_F;
ERROR 42000: Variable 'flush' can't be set to the value of 'TRUE_F'
SET @@global.flush = FALSE0;
ERROR 42000: Variable 'flush' can't be set to the value of 'FALSE0'
SET @@global.flush = OON;
ERROR 42000: Variable 'flush' can't be set to the value of 'OON'
SET @@global.flush = ONN;
ERROR 42000: Variable 'flush' can't be set to the value of 'ONN'
SET @@global.flush = OOFF;
ERROR 42000: Variable 'flush' can't be set to the value of 'OOFF'
SET @@global.flush = 0FF;
ERROR 42000: Variable 'flush' can't be set to the value of '0FF'
SET @@global.flush = ' ';
ERROR 42000: Variable 'flush' can't be set to the value of ' '
SET @@global.flush = " ";
ERROR 42000: Variable 'flush' can't be set to the value of ' '
SET @@global.flush = '';
ERROR 42000: Variable 'flush' can't be set to the value of ''
'#-------------------FN_DYNVARS_030_05----------------------------#'
SET @@session.flush = 1;
ERROR HY000: Variable 'flush' is a GLOBAL variable and should be set with SET GLOBAL
SELECT @@session.flush;
ERROR HY000: Variable 'flush' is a GLOBAL variable
'#----------------------FN_DYNVARS_030_06------------------------#'
SELECT IF(@@global.flush, "ON", "OFF") = VARIABLE_VALUE 
FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES 
WHERE VARIABLE_NAME='flush';
IF(@@global.flush, "ON", "OFF") = VARIABLE_VALUE
1
'#---------------------FN_DYNVARS_030_07----------------------#'
SET @@global.flush = TRUE;
SELECT @@global.flush;
@@global.flush
1
SET @@global.flush = FALSE;
SELECT @@global.flush;
@@global.flush
0
'#---------------------FN_DYNVARS_030_08----------------------#'
SET @@global.flush = 1;
SELECT @@flush = @@global.flush;
@@flush = @@global.flush
1
'#---------------------FN_DYNVARS_030_09----------------------#'
SET flush = 1;
ERROR HY000: Variable 'flush' is a GLOBAL variable and should be set with SET GLOBAL
SELECT global.flush;
ERROR 42S02: Unknown table 'global' in field list
SELECT flush = @@session.flush;
ERROR 42S22: Unknown column 'flush' in 'field list'
SET @@global.flush = @start_value;
SELECT @@global.flush;
@@global.flush
0