[mysqldumpslow 报错] Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. mysqldumpslow报错: Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. 总结:是因为top数目太多了,mysqldumpslow遍历不过来的缘故。 /usr/local/m
[mysqldumpslow 报错] Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236.mysqldumpslow报错:Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236.
总结:是因为top数目太多了,mysqldumpslow遍历不过来的缘故。
/usr/local/mysql/bin/mysqldumpslow -s -t 15 /root/db01-102-slow.log
1,把r去掉试试,还是报错,参数不识别。
[root@slave ]# /usr/local/mysql/bin/mysqldumpslow -s -t 15 /root/db01-102-slow.log Reading mysql slow query log from 15 /root/db01-102-slow.log Can't open 15: 没有那个文件或目录 at /usr/local/mysql/bin/mysqldumpslow line 91. Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [dubbo]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [dubbo]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [dubbo]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [dubbo]@[xx] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [dubbo]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S')
2,查看下mysqldumpslow 使用参数,-s后面需要带参数的,看了西夏at比较合适
[root@db-master-2 ~]# /usr/local/mysql/bin/mysqldumpslow --help Usage: mysqldumpslow [ OPTS... ] [ LOGS... ] Parse and summarize the MySQL slow query log. Options are --verbose verbose --debug debug --help write this text to standard output -v verbose -d debug -s ORDER what to sort by (al, at, ar, c, l, r, t), 'at' is default al: average lock time ar: average rows sent at: average query time c: count l: lock time r: rows sent t: query time -r reverse the sort order (largest last instead of first) -t NUM just show the top n queries -a don't abstract all numbers to N and strings to 'S' -n NUM abstract numbers with at least n digits within names -g PATTERN grep: only consider stmts that include this string -h HOSTNAME hostname of db server for *-slow.log filename (can be wildcard), default is '*', i.e. match all -i NAME name of server instance (if using mysql.server startup script) -l don't subtract lock time from total time
[root@db-master-2 ~]# /usr/local/mysql/bin/mysqldumpslow -s at -t 15 /root/db01-102-slow.log Reading mysql slow query log from /root/db01-102-slow.log Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [dubbo]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [dubbo]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S') Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [dubbo]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [dubbo]@[10.10.3.8] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [dubbo]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236.看到后面还是报错:Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236.
4,去看看/usr/local/mysql/bin/mysqldumpslow的第161行左右,到底是在操作什么脚本。
156 my @sorted = sort { $stmt{$b}->{$opt{s}} $stmt{$a}->{$opt{s}} } keys %stmt; 157 @sorted = @sorted[0 .. $opt{t}-1] if $opt{t}; 158 @sorted = reverse @sorted if $opt{r}; 159 160 foreach (@sorted) { 161 my $v = $stmt{$_} || die; 162 my ($c, $t,$at, $l,$al, $r,$ar) = @{ $v }{qw(c t at l al r ar)}; 163 my @users = keys %{$v->{users}}; 164 my $user = (@users==1) ? $users[0] : sprintf "%dusers",scalar @users; 165 my @hosts = keys %{$v->{hosts}}; 166 my $host = (@hosts==1) ? $hosts[0] : sprintf "%dhosts",scalar @hosts; 167 printf "Count: %d Time=%.2fs (%ds) Lock=%.2fs (%ds) Rows=%.1f (%d), $user\@$host\n%s\n\n", 168 $c, $at,$t, $al,$l, $ar,$r, $_; 169 } 170 171 sub usage { 172 my $str= shift;看到主要是foreach (@sorted)遍历函数,也就是遍历到chunk 236的时候就died结束了,没有办法往下继续foreach了。因为以前写过代码,知道报错所在的这一行
my $v = $stmt{$_} || die;是遍历第一句,那么肯定是赋值语句,报错Died,chunk 236肯定是已经遍历到末尾没有数据了,看这个函数没有判断传入的参数是否为null的逻辑,所以当文件数据已经遍历完,但是命令还没有结束,所以继续遍历,遍历null的时候报错,所以进程中止了,解决办法就是做个限制不要遍历超过原始数据的字符串长度。那么我们再来看执行的命令:
/usr/local/mysql/bin/mysqldumpslow -s at -t 15 /root/db01-102-slow.log 有 -t 15这一句,那么就是要显示出前15个记录,那么如果我的slow.log统计出来只有12个不到15个,而这里有继续遍历到15的话,那进程肯定会Died。
所以这里有2个解决方法:
1 修改/usr/local/mysql/bin/mysqldumpslow里面的源代码,加null判断。
这个过程有些复杂,暂时略过吧,期待后续空了再研究。
2 修改命令 /usr/local/mysql/bin/mysqldumpslow -s at -t 15 /root/db01-102-slow.log ,把-t 15修改成-t 10或者-t 5试试。
试了好几次,发现临界点在-t 7上面,如下:
[root@slave~]# /usr/local/mysql/bin/mysqldumpslow -s at -t 8 /root/db01-102-slow.log Reading mysql slow query log from /root/db01-102-slow.log Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [dubbo]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [dubbo]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S') Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [xx]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [xx]@[xxx] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [xx]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. -- 临界点 -t 7 [root@db-master-2 ~]# /usr/local/mysql/bin/mysqldumpslow -s at -t 7 /root/db01-102-slow.log Reading mysql slow query log from /root/db01-102-slow.log Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [xx]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [xx]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S') Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [xx]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [dubbo]@[xxx] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [dubbo]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) [root@db-master-2 ~]#
最终总结:
mysqldumpslow报错:Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. 是因为top数目太多了,mysqldumpslow遍历不过来的缘故。

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MySQL 느린 쿼리를 최적화하려면 SlowQueryLog 및 Performance_Schema를 사용해야합니다. 1. SlowQueryLog 및 Set Stresholds를 사용하여 느린 쿼리를 기록합니다. 2. Performance_schema를 사용하여 쿼리 실행 세부 정보를 분석하고 성능 병목 현상을 찾고 최적화하십시오.

MySQL 및 SQL은 개발자에게 필수적인 기술입니다. 1.MySQL은 오픈 소스 관계형 데이터베이스 관리 시스템이며 SQL은 데이터베이스를 관리하고 작동하는 데 사용되는 표준 언어입니다. 2.MYSQL은 효율적인 데이터 저장 및 검색 기능을 통해 여러 스토리지 엔진을 지원하며 SQL은 간단한 문을 통해 복잡한 데이터 작업을 완료합니다. 3. 사용의 예에는 기본 쿼리 및 조건 별 필터링 및 정렬과 같은 고급 쿼리가 포함됩니다. 4. 일반적인 오류에는 구문 오류 및 성능 문제가 포함되며 SQL 문을 확인하고 설명 명령을 사용하여 최적화 할 수 있습니다. 5. 성능 최적화 기술에는 인덱스 사용, 전체 테이블 스캔 피하기, 조인 작업 최적화 및 코드 가독성 향상이 포함됩니다.

MySQL 비동기 마스터 슬레이브 복제는 Binlog를 통한 데이터 동기화를 가능하게하여 읽기 성능 및 고 가용성을 향상시킵니다. 1) 마스터 서버 레코드는 Binlog로 변경됩니다. 2) 슬레이브 서버는 I/O 스레드를 통해 Binlog를 읽습니다. 3) 서버 SQL 스레드는 데이터를 동기화하기 위해 Binlog를 적용합니다.

MySQL은 오픈 소스 관계형 데이터베이스 관리 시스템입니다. 1) 데이터베이스 및 테이블 작성 : CreateAbase 및 CreateTable 명령을 사용하십시오. 2) 기본 작업 : 삽입, 업데이트, 삭제 및 선택. 3) 고급 운영 : 가입, 하위 쿼리 및 거래 처리. 4) 디버깅 기술 : 확인, 데이터 유형 및 권한을 확인하십시오. 5) 최적화 제안 : 인덱스 사용, 선택을 피하고 거래를 사용하십시오.

MySQL의 설치 및 기본 작업에는 다음이 포함됩니다. 1. MySQL 다운로드 및 설치, 루트 사용자 비밀번호를 설정하십시오. 2. SQL 명령을 사용하여 CreateAbase 및 CreateTable과 같은 데이터베이스 및 테이블을 만듭니다. 3. CRUD 작업을 실행하고 삽입, 선택, 업데이트, 명령을 삭제합니다. 4. 성능을 최적화하고 복잡한 논리를 구현하기 위해 인덱스 및 저장 절차를 생성합니다. 이 단계를 사용하면 MySQL 데이터베이스를 처음부터 구축하고 관리 할 수 있습니다.

innodbbufferpool은 데이터와 색인 페이지를 메모리에로드하여 MySQL 데이터베이스의 성능을 향상시킵니다. 1) 데이터 페이지가 버퍼 풀에로드되어 디스크 I/O를 줄입니다. 2) 더러운 페이지는 정기적으로 디스크로 표시되고 새로 고침됩니다. 3) LRU 알고리즘 관리 데이터 페이지 제거. 4) 읽기 메커니즘은 가능한 데이터 페이지를 미리로드합니다.

MySQL은 설치가 간단하고 강력하며 데이터를 쉽게 관리하기 쉽기 때문에 초보자에게 적합합니다. 1. 다양한 운영 체제에 적합한 간단한 설치 및 구성. 2. 데이터베이스 및 테이블 작성, 삽입, 쿼리, 업데이트 및 삭제와 같은 기본 작업을 지원합니다. 3. 조인 작업 및 하위 쿼리와 같은 고급 기능을 제공합니다. 4. 인덱싱, 쿼리 최적화 및 테이블 파티셔닝을 통해 성능을 향상시킬 수 있습니다. 5. 데이터 보안 및 일관성을 보장하기위한 지원 백업, 복구 및 보안 조치.


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