รายละเอียดตัวแปรทั้งหมด MySQL

เวลาเราต้องการสร้างตารางบน database สิ่งหนึ่งที่เป็นปัญหาของนักพัฒนาเว็บไซต์ นั่นคือ รายละเอียดของค่าตัวแปรแต่ละฟิล์ดว่าจะเลือกตัวไหนดี และมีอะไรบ้าง บทความนี้ได้รวบมตัวแปร หรือ system variable ต่างของระบบฐานข้อมูล MySQL มาให้เพื่อนๆ ได้นำไปศึกษาและใช้งานกันดู ?
คุณคิดว่า คุณสามารถจำค่าตัวแปรของ MySQL ได้ทั้งหมดหรือเปล่า ถ้ายังไม่แน่ใจ ลองหาคำตอบได้จากตารางด้านล่างต่อไปนี
MySQL System Variable Summary
Name |
Cmd- |
Option |
System |
Var |
Dyna |
auto_increment_increment | Yes | Yes | Yes | Both | Yes |
auto_increment_offset | Yes | Yes | Yes | Both | Yes |
autocommit | Yes | Yes | Yes | Session | Yes |
automatic_sp_privileges | Yes | Global | Yes | ||
back_log | Yes | Yes | Yes | Global | No |
basedir | Yes | Yes | Yes | Global | No |
bdb_cache_size | Yes | Yes | Yes | Global | No |
bdb-home | Yes | Yes | No | ||
– Variable: bdb_home | Yes | Global | No | ||
bdb-lock-detect | Yes | Yes | No | ||
– Variable: bdb_lock_detect | Yes | Global | No | ||
bdb_log_buffer_size | Yes | Yes | Yes | Global | No |
bdb-logdir | Yes | Yes | No | ||
– Variable: bdb_logdir | Yes | Global | No | ||
bdb_max_lock | Yes | Yes | Yes | Global | No |
bdb-shared-data | Yes | Yes | No | ||
– Variable: bdb_shared_data | Yes | Global | No | ||
bdb-tmpdir | Yes | Yes | No | ||
– Variable: bdb_tmpdir | Yes | Global | No | ||
big-tables | Yes | Yes | Yes | ||
– Variable: big_tables | Yes | Session | Yes | ||
bind-address | Yes | Yes | Yes | Global | No |
binlog_cache_size | Yes | Yes | Yes | Global | Yes |
bulk_insert_buffer_size | Yes | Yes | Yes | Both | Yes |
character_set_client | Yes | Both | Yes | ||
character_set_connection | Yes | Both | Yes | ||
character_set_database[a] | Yes | Both | Yes | ||
character-set-filesystem | Yes | Yes | Yes | ||
– Variable: character_set_filesystem | Yes | Both | Yes | ||
character_set_results | Yes | Both | Yes | ||
character-set-server | Yes | Yes | Yes | ||
– Variable: character_set_server | Yes | Both | Yes | ||
character_set_system | Yes | Global | No | ||
character-sets-dir | Yes | Yes | No | ||
– Variable: character_sets_dir | Yes | Global | No | ||
collation_connection | Yes | Both | Yes | ||
collation_database[b] | Yes | Both | Yes | ||
collation-server | Yes | Yes | Yes | ||
– Variable: collation_server | Yes | Both | Yes | ||
completion_type | Yes | Yes | Yes | Both | Yes |
concurrent_insert | Yes | Yes | Yes | Global | Yes |
connect_timeout | Yes | Yes | Yes | Global | Yes |
datadir | Yes | Yes | Yes | Global | No |
date_format | Yes | Both | No | ||
datetime_format | Yes | Both | No | ||
debug | Yes | Yes | Yes | Both | Yes |
default-storage-engine | Yes | Yes | Yes | Both | Yes |
default_week_format | Yes | Yes | Yes | Both | Yes |
delay-key-write | Yes | Yes | Yes | ||
– Variable: delay_key_write | Yes | Global | Yes | ||
delayed_insert_limit | Yes | Yes | Yes | Global | Yes |
delayed_insert_timeout | Yes | Yes | Yes | Global | Yes |
delayed_queue_size | Yes | Yes | Yes | Global | Yes |
div_precision_increment | Yes | Yes | Yes | Both | Yes |
engine-condition-pushdown | Yes | Yes | Yes | ||
– Variable: engine_condition_pushdown | Yes | Both | Yes | ||
error_count | Yes | Session | No | ||
expire_logs_days | Yes | Yes | Yes | Global | Yes |
flush | Yes | Yes | Yes | Global | Yes |
flush_time | Yes | Yes | Yes | Global | Yes |
foreign_key_checks | Yes | Session | Yes | ||
ft_boolean_syntax | Yes | Yes | Yes | Global | Yes |
ft_max_word_len | Yes | Yes | Yes | Global | No |
ft_min_word_len | Yes | Yes | Yes | Global | No |
ft_query_expansion_limit | Yes | Yes | Yes | Global | No |
ft_stopword_file | Yes | Yes | Yes | Global | No |
group_concat_max_len | Yes | Yes | Yes | Both | Yes |
have_archive | Yes | Global | No | ||
have_bdb | Yes | Global | No | ||
have_blackhole_engine | Yes | Global | No | ||
have_community_features | Yes | Global | No | ||
have_compress | Yes | Global | No | ||
have_crypt | Yes | Global | No | ||
have_csv | Yes | Global | No | ||
have_example_engine | Yes | Global | No | ||
have_federated_engine | Yes | Global | No | ||
have_geometry | Yes | Global | No | ||
have_innodb | Yes | Global | No | ||
have_isam | Yes | Global | No | ||
have_merge_engine | Yes | Global | No | ||
have_ndbcluster | Yes | Global | No | ||
have_openssl | Yes | Global | No | ||
have_profiling | Yes | Global | No | ||
have_query_cache | Yes | Global | No | ||
have_raid | Yes | Global | No | ||
have_rtree_keys | Yes | Global | No | ||
have_ssl | Yes | Global | No | ||
have_symlink | Yes | Global | No | ||
hostname | Yes | Global | No | ||
identity | Yes | Session | Yes | ||
init_connect | Yes | Yes | Yes | Global | Yes |
init-file | Yes | Yes | No | ||
– Variable: init_file | Yes | Global | No | ||
init_slave | Yes | Yes | Yes | Global | Yes |
innodb_adaptive_hash_index | Yes | Yes | Yes | Global | No |
innodb_additional_mem_pool_size | Yes | Yes | Yes | Global | No |
innodb_autoextend_increment | Yes | Yes | Yes | Global | Yes |
innodb_buffer_pool_awe_mem_mb | Yes | Yes | Yes | Global | No |
innodb_buffer_pool_size | Yes | Yes | Yes | Global | No |
innodb_checksums | Yes | Yes | Yes | Global | No |
innodb_commit_concurrency | Yes | Yes | Yes | Global | Yes |
innodb_concurrency_tickets | Yes | Yes | Yes | Global | Yes |
innodb_data_file_path | Yes | Yes | Yes | Global | No |
innodb_data_home_dir | Yes | Yes | Yes | Global | No |
innodb_doublewrite | Yes | Yes | Yes | Global | No |
innodb_fast_shutdown | Yes | Yes | Yes | Global | Yes |
innodb_file_io_threads | Yes | Yes | Yes | Global | No |
innodb_file_per_table | Yes | Yes | Yes | Global | No |
innodb_flush_log_at_trx_commit | Yes | Yes | Yes | Global | Yes |
innodb_flush_method | Yes | Yes | Yes | Global | No |
innodb_force_recovery | Yes | Yes | Yes | Global | No |
innodb_lock_wait_timeout | Yes | Yes | Yes | Global | No |
innodb_locks_unsafe_for_binlog | Yes | Yes | Yes | Global | No |
innodb_log_arch_dir | Yes | Yes | Yes | Global | No |
innodb_log_archive | Yes | Yes | Yes | Global | No |
innodb_log_buffer_size | Yes | Yes | Yes | Global | No |
innodb_log_file_size | Yes | Yes | Yes | Global | No |
innodb_log_files_in_group | Yes | Yes | Yes | Global | No |
innodb_log_group_home_dir | Yes | Yes | Yes | Global | No |
innodb_max_dirty_pages_pct | Yes | Yes | Yes | Global | Yes |
innodb_max_purge_lag | Yes | Yes | Yes | Global | Yes |
innodb_mirrored_log_groups | Yes | Yes | Yes | Global | No |
innodb_open_files | Yes | Yes | Yes | Global | No |
innodb_rollback_on_timeout | Yes | Yes | Yes | Global | No |
innodb_support_xa | Yes | Yes | Yes | Both | Yes |
innodb_sync_spin_loops | Yes | Yes | Yes | Global | Yes |
innodb_table_locks | Yes | Yes | Yes | Both | Yes |
innodb_thread_concurrency | Yes | Yes | Yes | Global | Yes |
innodb_thread_sleep_delay | Yes | Yes | Yes | Global | Yes |
innodb_use_legacy_cardinality_algorithm | Yes | Yes | Yes | Global | Yes |
insert_id | Yes | Session | Yes | ||
interactive_timeout | Yes | Yes | Yes | Both | Yes |
join_buffer_size | Yes | Yes | Yes | Both | Yes |
keep_files_on_create | Yes | Yes | Yes | Both | Yes |
key_buffer_size | Yes | Yes | Yes | Global | Yes |
key_cache_age_threshold | Yes | Yes | Yes | Global | Yes |
key_cache_block_size | Yes | Yes | Yes | Global | Yes |
key_cache_division_limit | Yes | Yes | Yes | Global | Yes |
language | Yes | Yes | Yes | Global | No |
large_files_support | Yes | Global | No | ||
large_page_size | Yes | Global | No | ||
large-pages | Yes | Yes | No | ||
– Variable: large_pages | Yes | Global | No | ||
last_insert_id | Yes | Session | Yes | ||
lc_time_names | Yes | Both | Yes | ||
license | Yes | Global | No | ||
local_infile | Yes | Global | Yes | ||
locked_in_memory | Yes | Global | No | ||
log | Yes | Yes | Yes | Global | No |
log_bin | Yes | Global | No | ||
log-bin | Yes | Yes | Yes | Global | No |
log-bin-trust-function-creators | Yes | Yes | Yes | ||
– Variable: log_bin_trust_function_creators | Yes | Global | Yes | ||
log-bin-trust-routine-creators | Yes | Yes | Yes | ||
– Variable: log_bin_trust_routine_creators | Yes | Global | Yes | ||
log-error | Yes | Yes | No | ||
– Variable: log_error | Yes | Global | No | ||
log-queries-not-using-indexes | Yes | Yes | Yes | ||
– Variable: log_queries_not_using_indexes | Yes | Global | Yes | ||
log-slave-updates | Yes | Yes | No | ||
– Variable: log_slave_updates | Yes | Global | No | ||
log_slave_updates | Yes | Yes | Yes | Global | No |
log-slow-queries | Yes | Yes | No | ||
– Variable: log_slow_queries | Yes | Global | No | ||
log-warnings | Yes | Yes | Yes | ||
– Variable: log_warnings | Yes | Both | Yes | ||
long_query_time | Yes | Yes | Yes | Both | Yes |
low-priority-updates | Yes | Yes | Yes | ||
– Variable: low_priority_updates | Yes | Both | Yes | ||
lower_case_file_system | Yes | Yes | Yes | Global | No |
lower_case_table_names | Yes | Yes | Yes | Global | No |
max_allowed_packet | Yes | Yes | Yes | Global | Yes |
max_binlog_cache_size | Yes | Yes | Yes | Global | Yes |
max_binlog_size | Yes | Yes | Yes | Global | Yes |
max_connect_errors | Yes | Yes | Yes | Global | Yes |
max_connections | Yes | Yes | Yes | Global | Yes |
max_delayed_threads | Yes | Yes | Yes | Both | Yes |
max_error_count | Yes | Yes | Yes | Both | Yes |
max_heap_table_size | Yes | Yes | Yes | Both | Yes |
max_insert_delayed_threads | Yes | Both | Yes | ||
max_join_size | Yes | Yes | Yes | Both | Yes |
max_length_for_sort_data | Yes | Yes | Yes | Both | Yes |
max_prepared_stmt_count | Yes | Yes | Yes | Global | Yes |
max_relay_log_size | Yes | Yes | Yes | Global | Yes |
max_seeks_for_key | Yes | Yes | Yes | Both | Yes |
max_sort_length | Yes | Yes | Yes | Both | Yes |
max_sp_recursion_depth | Yes | Yes | Yes | Both | Yes |
max_user_connections | Yes | Yes | Yes | Both | Yes |
max_write_lock_count | Yes | Yes | Yes | Global | Yes |
memlock | Yes | Yes | Yes | Global | No |
multi_range_count | Yes | Yes | Yes | Both | Yes |
myisam_data_pointer_size | Yes | Yes | Yes | Global | Yes |
myisam_max_extra_sort_file_size | Yes | Yes | Yes | Global | No |
myisam_max_sort_file_size | Yes | Yes | Yes | Global | Yes |
myisam_mmap_size | Yes | Yes | Yes | Global | No |
myisam_recover_options | Yes | Global | No | ||
myisam_repair_threads | Yes | Yes | Yes | Both | Yes |
myisam_sort_buffer_size | Yes | Yes | Yes | Both | Yes |
myisam_stats_method | Yes | Yes | Yes | Both | Yes |
named_pipe | Yes | Global | No | ||
ndb_autoincrement_prefetch_sz | Yes | Yes | Yes | Both | Yes |
ndb_cache_check_time | Yes | Yes | Yes | Global | Yes |
ndb_force_send | Yes | Yes | Yes | Both | Yes |
ndb_use_exact_count | Yes | Both | Yes | ||
ndb_use_transactions | Yes | Yes | Yes | Both | Yes |
net_buffer_length | Yes | Yes | Yes | Both | Yes |
net_read_timeout | Yes | Yes | Yes | Both | Yes |
net_retry_count | Yes | Yes | Yes | Both | Yes |
net_write_timeout | Yes | Yes | Yes | Both | Yes |
new | Yes | Yes | Yes | Both | Yes |
old_passwords | Yes | Both | Yes | ||
open-files-limit | Yes | Yes | No | ||
– Variable: open_files_limit | Yes | Global | No | ||
optimizer_prune_level | Yes | Yes | Yes | Both | Yes |
optimizer_search_depth | Yes | Yes | Yes | Both | Yes |
pid-file | Yes | Yes | No | ||
– Variable: pid_file | Yes | Global | No | ||
plugin_dir | Yes | Yes | Yes | Global | No |
port | Yes | Yes | Yes | Global | No |
preload_buffer_size | Yes | Yes | Yes | Both | Yes |
prepared_stmt_count | Yes | Global | No | ||
profiling | Yes | Session | Yes | ||
profiling_history_size | Yes | Yes | Yes | Both | Yes |
protocol_version | Yes | Global | No | ||
pseudo_thread_id | Yes | Session | Yes | ||
query_alloc_block_size | Yes | Yes | Yes | Both | Yes |
query_cache_limit | Yes | Yes | Yes | Global | Yes |
query_cache_min_res_unit | Yes | Yes | Yes | Global | Yes |
query_cache_size | Yes | Yes | Yes | Global | Yes |
query_cache_type | Yes | Yes | Yes | Both | Yes |
query_cache_wlock_invalidate | Yes | Yes | Yes | Both | Yes |
query_prealloc_size | Yes | Yes | Yes | Both | Yes |
rand_seed1 | Yes | Session | Yes | ||
rand_seed2 | Yes | Session | Yes | ||
range_alloc_block_size | Yes | Yes | Yes | Both | Yes |
read_buffer_size | Yes | Yes | Yes | Both | Yes |
read_only | Yes | Yes | Yes | Global | Yes |
read_rnd_buffer_size | Yes | Yes | Yes | Both | Yes |
relay-log | Yes | Yes | No | ||
– Variable: relay_log | Yes | Global | No | ||
relay-log-index | Yes | Yes | No | ||
– Variable: relay_log_index | Yes | Global | No | ||
relay_log_index | Yes | Yes | Yes | Global | No |
relay_log_info_file | Yes | Yes | Yes | Global | No |
relay_log_purge | Yes | Yes | Yes | Global | Yes |
relay_log_space_limit | Yes | Yes | Yes | Global | No |
report-host | Yes | Yes | No | ||
– Variable: report_host | Yes | Global | No | ||
report-password | Yes | Yes | No | ||
– Variable: report_password | Yes | Global | No | ||
report-port | Yes | Yes | No | ||
– Variable: report_port | Yes | Global | No | ||
report-user | Yes | Yes | No | ||
– Variable: report_user | Yes | Global | No | ||
rpl_recovery_rank | Yes | Global | Yes | ||
safe-show-database | Yes | Yes | Yes | Global | Yes |
secure-auth | Yes | Yes | Yes | ||
– Variable: secure_auth | Yes | Global | Yes | ||
secure-file-priv | Yes | Yes | No | ||
– Variable: secure_file_priv | Yes | Global | No | ||
server-id | Yes | Yes | Yes | ||
– Variable: server_id | Yes | Global | Yes | ||
shared_memory | Yes | Global | No | ||
shared_memory_base_name | Yes | Global | No | ||
skip-external-locking | Yes | Yes | No | ||
– Variable: skip_external_locking | Yes | Global | No | ||
skip-name-resolve | Yes | Yes | No | ||
– Variable: skip_name_resolve | Yes | Global | No | ||
skip-networking | Yes | Yes | No | ||
– Variable: skip_networking | Yes | Global | No | ||
skip-show-database | Yes | Yes | No | ||
– Variable: skip_show_database | Yes | Global | No | ||
skip-sync-bdb-logs | Yes | Yes | Yes | Global | No |
slave_compressed_protocol | Yes | Yes | Yes | Global | Yes |
slave-load-tmpdir | Yes | Yes | No | ||
– Variable: slave_load_tmpdir | Yes | Global | No | ||
slave-net-timeout | Yes | Yes | Yes | ||
– Variable: slave_net_timeout | Yes | Global | Yes | ||
slave-skip-errors | Yes | Yes | No | ||
– Variable: slave_skip_errors | Yes | Global | No | ||
slave_transaction_retries | Yes | Yes | Yes | Global | Yes |
slow_launch_time | Yes | Yes | Yes | Global | Yes |
socket | Yes | Yes | Yes | Global | No |
sort_buffer_size | Yes | Yes | Yes | Both | Yes |
sql_auto_is_null | Yes | Session | Yes | ||
sql_big_selects | Yes | Session | Yes | ||
sql_big_tables | Yes | Session | Yes | ||
sql_buffer_result | Yes | Session | Yes | ||
sql_log_bin | Yes | Session | Yes | ||
sql_log_off | Yes | Session | Yes | ||
sql_log_update | Yes | Session | Yes | ||
sql_low_priority_updates | Yes | Both | Yes | ||
sql_max_join_size | Yes | Both | Yes | ||
sql-mode | Yes | Yes | Yes | ||
– Variable: sql_mode | Yes | Both | Yes | ||
sql_notes | Yes | Session | Yes | ||
sql_quote_show_create | Yes | Session | Yes | ||
sql_safe_updates | Yes | Session | Yes | ||
sql_select_limit | Yes | Both | Yes | ||
sql_slave_skip_counter | Yes | Global | Yes | ||
sql_warnings | Yes | Session | Yes | ||
ssl-ca | Yes | Yes | No | ||
– Variable: ssl_ca | Yes | Global | No | ||
ssl-capath | Yes | Yes | No | ||
– Variable: ssl_capath | Yes | Global | No | ||
ssl-cert | Yes | Yes | No | ||
– Variable: ssl_cert | Yes | Global | No | ||
ssl-cipher | Yes | Yes | No | ||
– Variable: ssl_cipher | Yes | Global | No | ||
ssl-key | Yes | Yes | No | ||
– Variable: ssl_key | Yes | Global | No | ||
storage_engine | Yes | Both | Yes | ||
sync-bdb-logs | Yes | Yes | No | ||
– Variable: sync_bdb_logs | Yes | Global | No | ||
sync_binlog | Yes | Yes | Yes | Global | Yes |
sync_frm | Yes | Yes | Yes | Global | Yes |
system_time_zone | Yes | Global | No | ||
table_cache | Yes | Yes | Yes | Global | Yes |
table_lock_wait_timeout | Yes | Yes | Yes | Global | Yes |
table_type | Yes | Both | Yes | ||
thread_cache_size | Yes | Yes | Yes | Global | Yes |
thread_concurrency | Yes | Yes | Yes | Global | No |
thread_stack | Yes | Yes | Yes | Global | No |
time_format | Yes | Both | No | ||
time_zone | Yes | Yes | Yes | Both | Yes |
timed_mutexes | Yes | Yes | Yes | Global | Yes |
timestamp | Yes | Session | Yes | ||
tmp_table_size | Yes | Yes | Yes | Both | Yes |
tmpdir | Yes | Yes | Yes | Global | No |
transaction_alloc_block_size | Yes | Yes | Yes | Both | Yes |
transaction_prealloc_size | Yes | Yes | Yes | Both | Yes |
tx_isolation | Yes | Both | Yes | ||
unique_checks | Yes | Session | Yes | ||
updatable_views_with_limit | Yes | Yes | Yes | Both | Yes |
version | Yes | Global | No | ||
version_comment | Yes | Global | No | ||
version_compile_machine | Yes | Global | No | ||
version_compile_os | Yes | Global | No | ||
wait_timeout | Yes | Yes | Yes | Both | Yes |
warning_count | Yes | Session | No |
ที่มา : MySQL.com