Oracle 5.0 Reference Manual page 490

where keys are not used properly and that would probably take a long time. Set it if your users tend
to perform joins that lack a
Setting this variable to a value other than
to 0. If you set the
sql_big_selects
ignored.
If a query result is in the query cache, no result size check is performed, because the result has
previously been computed and it does not burden the server to send it to the client.
This variable previously was named sql_max_join_size.
•
max_length_for_sort_data
Command-Line Format
Option-File Format
Option Sets Variable
Variable Name
Variable Scope
Dynamic Variable
The cutoff on the size of index values that determines which
Section 8.3.1.11, "ORDER BY
•
max_prepared_stmt_count
Version Introduced
Command-Line Format
Option-File Format
Option Sets Variable
Variable Name
Variable Scope
Dynamic Variable
This variable limits the total number of prepared statements in the server. (The sum of the number of
prepared statements across all sessions.) It can be used in environments where there is the potential
for denial-of-service attacks based on running the server out of memory by preparing huge numbers
of statements. If the value is set lower than the current number of prepared statements, existing
statements are not affected and can be used, but no new statements can be prepared until the
current number drops below the limit. The default value is 16,382. The permissible range of values is
from 0 to 1 million. Setting the value to 0 disables prepared statements. This variable was added in
MySQL 5.0.21.
•
max_relay_log_size
Server System Variables
clause, that take a long time, or that return millions of rows.
WHERE
DEFAULT
[493] value again, the
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--max_length_for_sort_data=#
max_length_for_sort_data
Yes,
max_length_for_sort_data
max_length_for_sort_data
Global, Session
Yes
Permitted Values
Type
numeric
Default
1024
Range
4 .. 8388608
Optimization".
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5.0.21
--max_prepared_stmt_count=#
max_prepared_stmt_count
Yes,
max_prepared_stmt_count
max_prepared_stmt_count
Global
Yes
Permitted Values
Type
numeric
Default
16382
Range
0 .. 1048576
[470]
470
resets the value of
sql_big_selects
max_join_size
[470]
algorithm to use. See
filesort
[470]
[493]
[469] variable is