Server System Variables
487
Platform
Bit Size
64
Type
numeric
Default
8192
Range
8192 .. 18446744073709547520
Block
Size
1024
The size of the persistent buffer used for statement parsing and execution. This buffer is not freed
between statements. If you are running complex queries, a larger
query_prealloc_size
[486]
value might be helpful in improving performance, because it can reduce the need for the server to
perform memory allocation during query execution operations.
•
rand_seed1
[487]
The
rand_seed1
[487]
and
rand_seed2
[487]
variables exist as session variables only, and
can be set but not read. They are not shown in the output of
SHOW VARIABLES
.
The purpose of these variables is to support replication of the
RAND()
[912]
function. For
statements that invoke
RAND()
[912]
, the master passes two values to the slave, where they
are used to seed the random number generator. The slave uses these values to set the session
variables
rand_seed1
[487]
and
rand_seed2
[487]
so that
RAND()
[912]
on the slave
generates the same value as on the master.
•
rand_seed2
[487]
See the description for
rand_seed1
[487]
.
•
range_alloc_block_size
[487]
Command-Line Format
--range_alloc_block_size=#
Option-File Format
range_alloc_block_size
Option Sets Variable
Yes,
range_alloc_block_size
[487]
Variable Name
range_alloc_block_size
Variable Scope
Global, Session
Dynamic Variable
Yes
Permitted Values (>= 5.0.54)
Platform
Bit Size
32
Type
numeric
Default
4096
Range
4096 .. 4294967295
Block
Size
1024
Permitted Values (>= 5.0.54)
Platform
Bit Size
64
Type
numeric
Default
4096
Range
4096 .. 18446744073709547520
Содержание 5.0
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Страница 1842: ...Connector Net Installation 1822 5 Once the installation has been completed click Finish to exit the installer ...
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