MySQL :: MySQL 3.23, 4.0, 4.1 Reference Manual :: 5.1.1 Option and Variable Reference

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MySQL 3.23, 4.0, 4.1 Reference Manual :: 5 MySQL Server Administration :: 5.1 The MySQL Server :: 5.1.1 Option and Variable Reference

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5.1.1. Option and Variable Reference

The following table provides a list of all the command line options, server and status variables applicable within mysqld.

The table lists command-line options (Cmd-line), options valid in configuration files (Option file), server system variables (System Var), and status variables (Status var) in one unified list, with notification of where each option/variable is valid. If a server option set on the command line or in an option file differs from the name of the corresponding server system or status variable, the variable name is noted immediately below the corresponding option. For status variables, the scope of the variable is shown (Scope) as either global, session, or both. Please see the corresponding sections for details on setting and using the options and variables. Where appropriate, a direct link to further information on the item as available.

Note

This table is part of an ongoing process to expand and simplify the information provided on these elements. Further improvements to the table, and corresponding descriptions will be applied over the coming months.

Name	Cmd-Line	Option file	System Var	Dynamic
Aborted_clients				Yes	No
Aborted_connects				Yes	No
abort-slave-event-count	Yes	Yes
allow-suspicious-udfs	Yes	Yes
ansi	Yes	Yes
autocommit			Yes		Yes
back_log	Yes	Yes	Yes		No
basedir	Yes	Yes	Yes		No
bdb_cache_size	Yes	Yes	Yes		No
bdb-home	Yes	Yes	Yes		No
bdb-lock-detect	Yes	Yes			No
- Variable: bdb_lock_detect			Yes		No
bdb_log_buffer_size	Yes	Yes	Yes		No
bdb-logdir	Yes	Yes	Yes		No
bdb_max_lock	Yes	Yes	Yes		No
bdb-no-recover	Yes	Yes
bdb-no-sync	Yes	Yes
bdb-shared-data	Yes	Yes			No
- Variable: bdb_shared_data			Yes		No
bdb-tmpdir	Yes	Yes	Yes		No
big-tables	Yes	Yes			Yes
- Variable: big_tables			Yes		Yes
bind-address	Yes	Yes
Binlog_cache_disk_use				Yes	No
binlog_cache_size	Yes	Yes	Yes		Yes
Binlog_cache_use				Yes	No
binlog-do-db	Yes	Yes
binlog-ignore-db	Yes	Yes
bootstrap	Yes	Yes
bulk_insert_buffer_size	Yes	Yes	Yes		Yes
Bytes_received				Yes	No
Bytes_sent				Yes	No
character_set	Yes		Yes		No
character_set_client			Yes		Yes
character-set-client-handshake	Yes
character_set_connection			Yes		Yes
character_set_database			Yes		Yes
character_set_results			Yes		Yes
character-sets-dir	Yes	Yes			No
- Variable: character_sets_dir			Yes		No
character-set-server	Yes	Yes			Yes
- Variable: character_set_server			Yes		Yes
character_set_system			Yes		No
chroot	Yes	Yes
collation_connection			Yes		Yes
collation_database			Yes		Yes
collation-server	Yes	Yes			Yes
- Variable: collation_server			Yes		Yes
Com_admin_commands				Yes	No
Com_alter_db				Yes	No
Com_alter_table				Yes	No
Com_analyze				Yes	No
Com_backup_table				Yes	No
Com_begin				Yes	No
Com_change_db				Yes	No
Com_change_master				Yes	No
Com_check				Yes	No
Com_checksum				Yes	No
Com_commit				Yes	No
Com_create_db				Yes	No
Com_create_index				Yes	No
Com_create_table				Yes	No
Com_dealloc_sql				Yes	No
Com_delete				Yes	No
Com_delete_multi				Yes	No
Com_do				Yes	No
Com_drop_db				Yes	No
Com_drop_index				Yes	No
Com_drop_table				Yes	No
Com_drop_user				Yes	No
Com_execute_sql				Yes	No
Com_flush				Yes	No
Com_grant				Yes	No
Com_ha_close				Yes	No
Com_ha_open				Yes	No
Com_ha_read				Yes	No
Com_help				Yes	No
Com_insert				Yes	No
Com_insert_select				Yes	No
Com_kill				Yes	No
Com_load				Yes	No
Com_load_master_data				Yes	No
Com_load_master_table				Yes	No
Com_lock_tables				Yes	No
Com_optimize				Yes	No
Com_preload_keys				Yes	No
Com_prepare_sql				Yes	No
Com_rename_table				Yes	No
Com_repair				Yes	No
Com_replace				Yes	No
Com_replace_select				Yes	No
Com_reset				Yes	No
Com_restore_table				Yes	No
Com_revoke				Yes	No
Com_revoke_all				Yes	No
Com_rollback				Yes	No
Com_savepoint				Yes	No
Com_select				Yes	No
Com_set_option				Yes	No
Com_show_binlog_events				Yes	No
Com_show_binlogs				Yes	No
Com_show_charsets				Yes	No
Com_show_collations				Yes	No
Com_show_column_types				Yes	No
Com_show_create_db				Yes	No
Com_show_create_event				Yes	No
Com_show_create_table				Yes	No
Com_show_databases				Yes	No
Com_show_engine_logs				Yes	No
Com_show_engine_mutex				Yes	No
Com_show_engine_status				Yes	No
Com_show_errors				Yes	No
Com_show_fields				Yes	No
Com_show_grants				Yes	No
Com_show_innodb_status				Yes	No
Com_show_keys				Yes	No
Com_show_logs				Yes	No
Com_show_master_status				Yes	No
Com_show_ndb_status				Yes	No
Com_show_new_master				Yes	No
Com_show_open_tables				Yes	No
Com_show_privileges				Yes	No
Com_show_processlist				Yes	No
Com_show_slave_hosts				Yes	No
Com_show_slave_status				Yes	No
Com_show_status				Yes	No
Com_show_storage_engines				Yes	No
Com_show_tables				Yes	No
Com_show_variables				Yes	No
Com_show_warnings				Yes	No
Com_slave_start				Yes	No
Com_slave_stop				Yes	No
Com_stmt_close				Yes	No
Com_stmt_execute				Yes	No
Com_stmt_fetch				Yes	No
Com_stmt_prepare				Yes	No
Com_stmt_reset				Yes	No
Com_stmt_send_long_data				Yes	No
Com_truncate				Yes	No
Com_unlock_tables				Yes	No
Com_update				Yes	No
Com_update_multi				Yes	No
concurrent_insert	Yes	Yes	Yes		Yes
connect_timeout	Yes	Yes	Yes		Yes
console	Yes	Yes
core-file	Yes	Yes
crash_binlog_innodb	Yes	Yes
Created_tmp_disk_tables				Yes	No
Created_tmp_files				Yes	No
Created_tmp_tables				Yes	No
datadir	Yes	Yes	Yes		No
date_format			Yes		Yes
datetime_format	Yes	Yes	Yes		Yes
debug	Yes	Yes	Yes		Yes
default-character-set	Yes	Yes
default-collation	Yes		Yes		No
defaults-extra-file	Yes
defaults-file	Yes
default-storage-engine	Yes	Yes
default-table-type	Yes	Yes
default-time-zone	Yes	Yes
default_week_format	Yes	Yes	Yes		Yes
delayed_insert_limit	Yes	Yes	Yes		Yes
delayed_insert_timeout	Yes	Yes	Yes		Yes
delayed_queue_size	Yes	Yes	Yes		Yes
delay-key-write	Yes	Yes			Yes
- Variable: delay_key_write			Yes		Yes
des-key-file	Yes	Yes
disconnect-slave-event-count	Yes	Yes
enable-locking	Yes
enable-pstack	Yes	Yes
error_count			Yes		No
exit-info	Yes	Yes
expire_logs_days	Yes	Yes	Yes		Yes
external-locking	Yes	Yes
- Variable: external_locking
flush	Yes	Yes	Yes		Yes
flush_time	Yes	Yes	Yes		Yes
foreign_key_checks			Yes		Yes
ft_boolean_syntax	Yes	Yes	Yes		Yes
ft_max_word_len	Yes	Yes	Yes		No
ft_min_word_len	Yes	Yes	Yes		No
ft_query_expansion_limit	Yes	Yes	Yes		No
ft_stopword_file	Yes	Yes	Yes		No
gdb	Yes	Yes
group_concat_max_len	Yes	Yes	Yes		Yes
Handler_commit				Yes	No
Handler_delete				Yes	No
Handler_discover				Yes	No
Handler_read_first				Yes	No
Handler_read_key				Yes	No
Handler_read_next				Yes	No
Handler_read_prev				Yes	No
Handler_read_rnd				Yes	No
Handler_read_rnd_next				Yes	No
Handler_rollback				Yes	No
Handler_update				Yes	No
Handler_write				Yes	No
have_archive			Yes		No
have_bdb			Yes		No
have_blackhole_engine			Yes		No
have_compress			Yes		No
have_crypt			Yes		No
have_csv			Yes		No
have_example_engine			Yes		No
have_geometry			Yes		No
have_innodb			Yes		No
have_isam			Yes		No
have_merge_engine			Yes		No
have_ndbcluster			Yes		No
have_openssl			Yes		No
have_query_cache			Yes		No
have_raid			Yes		No
have_rtree_keys			Yes		No
have_symlink			Yes		No
help	Yes
identity			Yes		Yes
init_connect	Yes	Yes	Yes		Yes
init-file	Yes	Yes			No
- Variable: init_file			Yes		No
init_slave	Yes	Yes	Yes		Yes
innodb	Yes	Yes
innodb_additional_mem_pool_size	Yes	Yes	Yes		No
innodb_autoextend_increment	Yes	Yes	Yes		Yes
innodb_buffer_pool_awe_mem_mb	Yes	Yes	Yes		No
innodb_buffer_pool_size	Yes	Yes	Yes		No
innodb_data_file_path	Yes	Yes	Yes		No
innodb_data_home_dir	Yes	Yes	Yes		No
innodb_fast_shutdown	Yes	Yes	Yes		Yes
innodb_file_io_threads	Yes	Yes	Yes		No
innodb_file_per_table	Yes	Yes	Yes		No
innodb_flush_log_at_trx_commit	Yes	Yes	Yes		Yes
innodb_flush_method	Yes	Yes	Yes		No
innodb_force_recovery	Yes	Yes	Yes		No
innodb_locks_unsafe_for_binlog	Yes	Yes	Yes		No
innodb_lock_wait_timeout	Yes	Yes	Yes		No
innodb_log_arch_dir	Yes	Yes	Yes		No
innodb_log_archive	Yes	Yes	Yes		No
innodb_log_buffer_size	Yes	Yes	Yes		No
innodb_log_files_in_group	Yes	Yes	Yes		No
innodb_log_file_size	Yes	Yes	Yes		No
innodb_log_group_home_dir	Yes	Yes	Yes		No
innodb_max_dirty_pages_pct	Yes	Yes	Yes		Yes
innodb_max_purge_lag	Yes	Yes	Yes		Yes
innodb_mirrored_log_groups	Yes	Yes	Yes		No
innodb_open_files	Yes	Yes	Yes		No
innodb_status_file	Yes	Yes	Yes		No
innodb_table_locks	Yes	Yes	Yes		Yes
innodb_thread_concurrency	Yes	Yes	Yes		Yes
insert_id			Yes		Yes
interactive_timeout	Yes	Yes	Yes		Yes
isam	Yes	Yes	Yes		No
join_buffer_size	Yes	Yes	Yes		Yes
Key_blocks_not_flushed				Yes	No
Key_blocks_unused				Yes	No
Key_blocks_used				Yes	No
key_buffer_size	Yes	Yes	Yes		Yes
key_cache_age_threshold	Yes	Yes	Yes		Yes
key_cache_block_size	Yes	Yes	Yes		Yes
key_cache_division_limit	Yes	Yes	Yes		Yes
Key_read_requests				Yes	No
Key_reads				Yes	No
Key_write_requests				Yes	No
Key_writes				Yes	No
language	Yes	Yes	Yes		No
last_insert_id			Yes		Yes
lc_time_names			Yes		Yes
license			Yes		No
local_infile			Yes		Yes
local-infile	Yes	Yes
locked_in_memory			Yes		No
log	Yes	Yes	Yes		No
log_bin			Yes		No
log-bin	Yes	Yes
log-bin-index	Yes	Yes
log-error	Yes	Yes			No
- Variable: log_error			Yes		No
log-isam	Yes	Yes
log-long-format	Yes	Yes
log-queries-not-using-indexes	Yes	Yes			Yes
- Variable: log_queries_not_using_indexes			Yes		Yes
log-short-format	Yes	Yes
log-slave-updates	Yes	Yes			No
- Variable: log_slave_updates			Yes		No
log-slow-admin-statements	Yes	Yes
log-slow-queries	Yes	Yes			No
- Variable: log_slow_queries			Yes		No
log-update	Yes
log-warnings	Yes	Yes			Yes
- Variable: log_warnings			Yes		Yes
long_query_time	Yes	Yes	Yes		Yes
lower_case_file_system	Yes	Yes	Yes		No
lower_case_table_names	Yes	Yes	Yes		No
low-priority-updates	Yes	Yes			Yes
- Variable: low_priority_updates			Yes		Yes
master-connect-retry	Yes	Yes
master-host	Yes	Yes
master-info-file	Yes	Yes
master-password	Yes	Yes
master-port	Yes	Yes
master-retry-count	Yes	Yes
master-ssl	Yes	Yes
master-ssl-ca	Yes	Yes
master-ssl-capath	Yes	Yes
master-ssl-cert	Yes	Yes
master-ssl-cipher	Yes	Yes
master-ssl-key	Yes	Yes
master-user	Yes	Yes
max_allowed_packet	Yes	Yes	Yes		Yes
max_binlog_cache_size	Yes	Yes	Yes		Yes
max-binlog-dump-events	Yes	Yes
max_binlog_size	Yes	Yes	Yes		Yes
max_connect_errors	Yes	Yes	Yes		Yes
max_connections	Yes	Yes	Yes		Yes
max_delayed_threads	Yes	Yes	Yes		Yes
max_error_count	Yes	Yes	Yes		Yes
max_heap_table_size	Yes	Yes	Yes		Yes
max_insert_delayed_threads			Yes		Yes
max_join_size	Yes	Yes	Yes		Yes
max_length_for_sort_data	Yes	Yes	Yes		Yes
max_prepared_stmt_count	Yes	Yes	Yes		Yes
max_relay_log_size	Yes	Yes	Yes		Yes
max_seeks_for_key	Yes	Yes	Yes		Yes
max_sort_length	Yes	Yes	Yes		Yes
max_tmp_tables	Yes	Yes	Yes		Yes
Max_used_connections				Yes	No
max_user_connections	Yes	Yes	Yes		Yes
max_write_lock_count	Yes	Yes	Yes		Yes
memlock	Yes	Yes	Yes		No
merge	Yes	Yes
myisam_block_size	Yes	Yes	Yes		Yes
myisam_data_pointer_size	Yes	Yes	Yes		Yes
myisam_max_extra_sort_file_size	Yes	Yes	Yes		No
myisam_max_sort_file_size	Yes	Yes	Yes		Yes
myisam-recover	Yes	Yes
myisam_recover_options			Yes		No
myisam_repair_threads	Yes	Yes	Yes		Yes
myisam_sort_buffer_size	Yes	Yes	Yes		Yes
myisam_stats_method	Yes	Yes	Yes		Yes
named_pipe			Yes		No
ndb_autoincrement_prefetch_sz	Yes	Yes	Yes		Yes
ndb_cache_check_time	Yes	Yes	Yes		Yes
ndbcluster	Yes	Yes	Yes		Yes
ndb_force_send	Yes	Yes	Yes		Yes
ndb_index_stat_cache_entries	Yes	Yes
ndb_index_stat_enable	Yes	Yes
ndb_index_stat_update_freq	Yes	Yes
ndb_optimized_node_selection	Yes	Yes
ndb_report_thresh_binlog_epoch_slip	Yes	Yes
ndb_report_thresh_binlog_mem_usage	Yes	Yes
ndb_use_exact_count			Yes		Yes
ndb_use_transactions	Yes	Yes
net_buffer_length	Yes	Yes	Yes		Yes
net_read_timeout	Yes	Yes	Yes		Yes
net_retry_count	Yes	Yes	Yes		Yes
net_write_timeout	Yes	Yes	Yes		Yes
new	Yes	Yes	Yes		Yes
no-defaults	Yes
Not_flushed_delayed_rows				Yes	No
old-passwords	Yes	Yes			Yes
- Variable: old_passwords			Yes		Yes
old-protocol	Yes	Yes
Opened_tables				Yes	No
Open_files				Yes	No
open-files-limit	Yes	Yes			No
- Variable: open_files_limit			Yes		No
Open_streams				Yes	No
Open_tables				Yes	No
pid-file	Yes	Yes			No
- Variable: pid_file			Yes		No
port	Yes	Yes	Yes		No
preload_buffer_size	Yes	Yes	Yes		Yes
prepared_stmt_count			Yes	Yes	No
print-defaults	Yes
protocol_version			Yes		No
Qcache_free_blocks				Yes	No
Qcache_free_memory				Yes	No
Qcache_hits				Yes	No
Qcache_inserts				Yes	No
Qcache_lowmem_prunes				Yes	No
Qcache_not_cached				Yes	No
Qcache_queries_in_cache				Yes	No
Qcache_total_blocks				Yes	No
query_alloc_block_size	Yes	Yes	Yes		Yes
query_cache_limit	Yes	Yes	Yes		Yes
query_cache_min_res_unit	Yes	Yes	Yes		Yes
query_cache_size	Yes	Yes	Yes		Yes
query_cache_type	Yes	Yes	Yes		Yes
query_cache_wlock_invalidate	Yes	Yes	Yes		Yes
query_prealloc_size	Yes	Yes	Yes		Yes
Questions				Yes	No
range_alloc_block_size	Yes	Yes	Yes		Yes
read_buffer_size	Yes	Yes	Yes		Yes
read_only	Yes	Yes	Yes		Yes
read_rnd_buffer_size	Yes	Yes	Yes		Yes
relay-log	Yes	Yes
relay-log-index	Yes	Yes
relay-log-info-file	Yes	Yes
relay_log_purge	Yes	Yes	Yes		Yes
relay_log_space_limit	Yes	Yes	Yes		No
replicate-do-db	Yes	Yes
replicate-do-table	Yes	Yes
replicate-ignore-db	Yes	Yes
replicate-ignore-table	Yes	Yes
replicate-rewrite-db	Yes	Yes
replicate-same-server-id	Yes	Yes
replicate-wild-do-table	Yes	Yes
replicate-wild-ignore-table	Yes	Yes
report-host	Yes	Yes			No
- Variable: report_host			Yes		No
report-password	Yes	Yes			No
- Variable: report_password			Yes		No
report-port	Yes	Yes			No
- Variable: report_port			Yes		No
report-user	Yes	Yes			No
- Variable: report_user			Yes		No
rpl_recovery_rank			Yes		Yes
safemalloc-mem-limit	Yes	Yes
safe-mode	Yes	Yes
safe-show-database	Yes	Yes			Yes
- Variable: safe_show_database			Yes		Yes
safe-user-create	Yes	Yes
secure-auth	Yes	Yes			Yes
- Variable: secure_auth			Yes		Yes
Select_full_join				Yes	No
Select_full_range_join				Yes	No
Select_range				Yes	No
Select_range_check				Yes	No
Select_scan				Yes	No
server-id	Yes	Yes</