MySQL分析執(zhí)行次數(shù)最多的SQL的六種方法
在MySQL中分析執(zhí)行次數(shù)最多的SQL,主要有以下幾種方法:
1. 使用MySQL慢查詢?nèi)罩?/h2>
開啟慢查詢?nèi)罩?/h3>
-- 查看慢查詢配置
SHOW VARIABLES LIKE 'slow_query_log%';
SHOW VARIABLES LIKE 'long_query_time';
-- 開啟慢查詢?nèi)罩荆ㄐ柙趍y.cnf中配置持久化)
SET GLOBAL slow_query_log = 1;
SET GLOBAL long_query_time = 1; -- 設(shè)置慢查詢閾值(秒)
SET GLOBAL slow_query_log_file = '/var/log/mysql/slow.log';
-- 查看慢查詢配置 SHOW VARIABLES LIKE 'slow_query_log%'; SHOW VARIABLES LIKE 'long_query_time'; -- 開啟慢查詢?nèi)罩荆ㄐ柙趍y.cnf中配置持久化) SET GLOBAL slow_query_log = 1; SET GLOBAL long_query_time = 1; -- 設(shè)置慢查詢閾值(秒) SET GLOBAL slow_query_log_file = '/var/log/mysql/slow.log';
使用mysqldumpslow分析
# 分析執(zhí)行次數(shù)最多的慢查詢 mysqldumpslow -s c -t 10 /var/log/mysql/slow.log # 按執(zhí)行時(shí)間排序 mysqldumpslow -s t -t 10 /var/log/mysql/slow.log
2. 使用Performance Schema
開啟Performance Schema
-- 檢查是否開啟 SHOW VARIABLES LIKE 'performance_schema'; -- 開啟events_statements_history(如果未開啟) UPDATE performance_schema.setup_consumers SET ENABLED = 'YES' WHERE NAME LIKE 'events_statements_history%';
查詢執(zhí)行次數(shù)最多的SQL
SELECT
DIGEST_TEXT AS query,
COUNT_STAR AS exec_count,
AVG_TIMER_WAIT/1000000000000 AS avg_exec_time_sec,
SUM_ROWS_EXAMINED AS rows_examined_sum,
SUM_ROWS_SENT AS rows_sent_sum
FROM performance_schema.events_statements_summary_by_digest
WHERE DIGEST_TEXT IS NOT NULL
ORDER BY COUNT_STAR DESC
LIMIT 10;
3. 使用Sys Schema(MySQL 5.7+)
-- 查看執(zhí)行次數(shù)最多的語句
SELECT * FROM sys.statements_with_full_table_scans
ORDER BY exec_count DESC
LIMIT 10;
-- 查看總執(zhí)行次數(shù)最多的語句
SELECT * FROM sys.statement_analysis
ORDER BY exec_count DESC
LIMIT 10;
-- 查看執(zhí)行次數(shù)多的標(biāo)準(zhǔn)化SQL
SELECT
query,
db,
exec_count,
total_latency,
avg_latency,
rows_sent_avg,
rows_examined_avg
FROM sys.x$statements_with_runtimes_in_95th_percentile
ORDER BY exec_count DESC
LIMIT 10;
4. 使用通用日志(不推薦生產(chǎn)環(huán)境)
-- 開啟通用查詢?nèi)罩?
SET GLOBAL general_log = 1;
SET GLOBAL general_log_file = '/var/log/mysql/general.log';
-- 分析日志(示例使用awk)
awk '
{
if ($0 ~ /Query/) {
# 提取SQL語句(簡(jiǎn)化版)
query = substr($0, index($0, "Query:") + 7)
queries[query]++
}
}
END {
for (q in queries) {
print queries[q] " " q
}
}' /var/log/mysql/general.log | sort -nr | head -10
5. 使用INFORMATION_SCHEMA.PROCESSLIST(實(shí)時(shí)監(jiān)控)
-- 查看當(dāng)前執(zhí)行的SQL
SELECT
INFO AS query,
COUNT(*) AS concurrent_count
FROM INFORMATION_SCHEMA.PROCESSLIST
WHERE COMMAND = 'Query'
AND INFO IS NOT NULL
GROUP BY INFO
ORDER BY concurrent_count DESC
LIMIT 10;
6. 使用pt-query-digest工具
# 分析慢查詢?nèi)罩? pt-query-digest /var/log/mysql/slow.log # 分析tcpdump抓取的流量 tcpdump -i any -s 65535 -x -nn -q -tttt port 3306 > mysql.tcp.txt pt-query-digest --type tcpdump mysql.tcp.txt # 分析general log pt-query-digest --type genlog /var/log/mysql/general.log
推薦的生產(chǎn)環(huán)境方案
對(duì)于生產(chǎn)環(huán)境,建議組合使用:
- 長期監(jiān)控:Performance Schema + Sys Schema
- 性能分析:慢查詢?nèi)罩?+ pt-query-digest
- 實(shí)時(shí)監(jiān)控:INFORMATION_SCHEMA.PROCESSLIST
完整的Performance Schema監(jiān)控示例
-- 開啟必要的監(jiān)控項(xiàng)
UPDATE performance_schema.setup_instruments
SET ENABLED = 'YES', TIMED = 'YES'
WHERE NAME LIKE 'statement/%';
UPDATE performance_schema.setup_consumers
SET ENABLED = 'YES'
WHERE NAME LIKE '%statements%';
-- 定期查詢TOP SQL(可做成定時(shí)任務(wù))
SELECT
SCHEMA_NAME as db,
DIGEST_TEXT as query,
COUNT_STAR as exec_count,
ROUND(SUM_TIMER_WAIT/1000000000000, 2) as total_time_sec,
ROUND(AVG_TIMER_WAIT/1000000000000, 4) as avg_time_sec,
SUM_ROWS_EXAMINED as rows_examined,
SUM_ROWS_SENT as rows_sent,
FIRST_SEEN as first_seen,
LAST_SEEN as last_seen
FROM performance_schema.events_statements_summary_by_digest
WHERE DIGEST_TEXT IS NOT NULL
AND COUNT_STAR > 0
ORDER BY COUNT_STAR DESC
LIMIT 20;
選擇哪種方法取決于你的具體需求:實(shí)時(shí)監(jiān)控用Performance Schema,深度分析用慢查詢?nèi)罩?,快速排查用Sys Schema。
以上就是MySQL分析執(zhí)行次數(shù)最多的SQL的六種方法的詳細(xì)內(nèi)容,更多關(guān)于MySQL執(zhí)行次數(shù)最多的SQL的資料請(qǐng)關(guān)注腳本之家其它相關(guān)文章!
相關(guān)文章
云服務(wù)器Ubuntu_Server_16.04.1安裝MySQL并開啟遠(yuǎn)程連接的方法
這篇文章主要介紹了云服務(wù)器Ubuntu_Server_16.04.1安裝MySQL并開啟遠(yuǎn)程連接的方法,非常不錯(cuò),具有參考借鑒價(jià)值,需要的朋友可以參考下2018-02-02
優(yōu)化mysql數(shù)據(jù)庫的經(jīng)驗(yàn)總結(jié)
本篇文章是對(duì)優(yōu)化mysql數(shù)據(jù)庫的經(jīng)驗(yàn)進(jìn)行了詳細(xì)的總結(jié)介紹,需要的朋友參考下2013-06-06
infobright導(dǎo)入數(shù)據(jù)遇到特殊字符報(bào)錯(cuò)的解決方法
這篇文章主要介紹了infobright導(dǎo)入數(shù)據(jù)遇到特殊字符報(bào)錯(cuò)的解決方法,Infobright是開源的MySQL數(shù)據(jù)倉庫解決方案,需要的朋友可以參考下2014-07-07
分享幾道關(guān)于MySQL索引的重點(diǎn)面試題
這篇文章主要給大家介紹了幾道關(guān)于MySQL索引的重點(diǎn)面試題,文中通過示例代碼介紹的非常詳細(xì),對(duì)大家學(xué)習(xí)或者使用MySQL具有一定的參考學(xué)習(xí)價(jià)值,需要的朋友們下面來一起學(xué)習(xí)學(xué)習(xí)吧2019-05-05
MySQL安裝提示"請(qǐng)鍵入NET HELPMSG 3534以獲得更多的幫助"的解決辦法
這篇文章主要介紹了MySQL安裝提示"請(qǐng)鍵入NET HELPMSG 3534以獲得更多的幫助"的解決辦法2017-03-03

