FAILED TO READ MORROR SIDE 1 问题描述: 环境: RAC p740 p550 -bash-3.2$ srvctl status database -d kmis Instance kmis1 is running on node p550 Instance kmis2 is not running on node p740 AIX -bash-3.2$ oslevel -r 6100-08 数据库 oracle 11.2.2
FAILED TO READ MORROR SIDE 1
问题描述:
环境:
RAC p740 p550
-bash-3.2$ srvctl status database -d kmis
Instance kmis1 is running on node p550
Instance kmis2 is not running on node p740
AIX
-bash-3.2$ oslevel -r
6100-08
数据库 oracle 11.2.2
$ srvctl start database -d kmis
PRCR-1079 : Failed to start resource ora.kmis.db
CRS-5017: The resource action "ora.ARCHDG.dg start" encountered the following error:
ORA-15032: not all alterations performed
ORA-15017: diskgroup "ARCHDG" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "ARCHDG"
ORA-15080: synchronous I/O operation to a disk failed
CRS-2674: Start of 'ora.ARCHDG.dg' on 'p740' failed
CRS-2632: There are no more servers to try to place resource 'ora.kmis.db' on that would satisfy its placement policy
$
$ srvctl start instance -d kmis -i kmis2 -o open;
PRCR-1013 : Failed to start resource ora.kmis.db
PRCR-1064 : Failed to start resource ora.kmis.db on node p740
CRS-5017: The resource action "ora.ARCHDG.dg start" encountered the following error:
ORA-15032: not all alterations performed
ORA-15017: diskgroup "ARCHDG" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "ARCHDG"
ORA-15080: synchronous I/O operation to a disk failed
1
p550
ASMCMD> ls -lState Type Rebal NameMOUNTED EXTERN N ARCHDG/MOUNTED NORMAL N CRS/MOUNTED EXTERN N DATADG/ASMCMD> host
p740上
MOUNTED NORMAL N CRS/MOUNTED EXTERN N DATADG/挂载不上 ARCDG
一挂载就报错
odm:
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B - Defect | 12.1 | ||
2 - Severe Loss of Service | 11.2.0.1 | ||
90 - Closed, Verified by Filer | 212 - IBM AIX on POWER Systems (64-bit) | ||
2010-12-22 | |||
2014-3-19 | N/A | ||
11.2.0.1 | Generic | ||
Oracle |

|
Oracle Database Products | Oracle Database Suite | ||
Oracle Database | 5 - Oracle Database - Enterprise Edition | ||

Hdr: 10422126 11.2.0.1 RDBMS 11.2.0.1 ASM PRODID-5 PORTID-212 Abstract: FAILED TO READ MORROR SIDE 1 <strong>*** 12/22/10 03:46 am ***</strong> ---- PROBLEM: -------- Alert log spooling this error continously and filling up available space. Here is the message. ----------------------- WARNING: failed to read mirror side 1 of virtual extent 665 logical extent 0 of file 280 in group [1.445758315] from disk ASM_ESBQA001_DATA1_0005 allocation unit 75811 reason error; if possible,will try another mirror side ----------------------- When the problem starts, errors spin in the alert log until disk space is exausted. We have found that the process that is refrenced in the trace is usually an orphaned ebiz form. Recent Changes - Upgrade to 11.2.0.1 Over the weekend we have upgraded Production Database to 11.2.0.1. We've had 2 occurrence of the issue on 2 of the RAC nodes. The issue had happened in QA and we have tried to drop the disk and add new disk again, but it did not solve the problem. One more thing to note is, when this happens, there was a "run-away" process that also generates the same error message in a trace file. As long as that session/process is killed, the error messages stops. Please investigate. DIAGNOSTIC ANALYSIS: -------------------- This looks closely related to bug.10051315 and bug.10055063 But customer has applied these patches already, even then we still see the same warning messages. We are still trying to get information from customer to understand how that session is being killed(not sure could be from database end --or application end). Customer confirmed the following : --------------- 1.) Are they in-house scripts scheduled in database/os which are going to kill the inactive sessions at database/os level ? -- There are not any scripts scheduled to kill sessions. When this error starts happening, we kill the process manually. 2.) Is this happening only during specific intervals. -- I cannot see a pattern as to when it is happening. It seems random. 3.) Please confirm - the ASM instance is functional (one can connect to it, run queries on the various v$asm% views, like: v$asm_diskgroup, v$asm_disk) -- Yes, ASM is functional during the error. All other sessions continue to run without errors. --------------- WORKAROUND: ----------- As long as that session/process is killed, the error messages stops. RELATED BUGS: ------------- bug.10051315 and bug.10055063 REPRODUCIBILITY: ---------------- Its random. TEST CASE: ---------- NA STACK TRACE: ------------ Function List (to Full stack) (to Summary stack) ksedsts <- ksdxfstk <- ksdxcb <- sspuser <- f0 <- sdbgrfucf_close_file <- sdbgrfcf_close_file <- dbgrlWriteTextOnly <- dbgrlWriteAlertDetail_int <- dbgrlWriteAlertDetail <- dbgrlWriteAlertText <- dbkrlWriteAlertText <- dbkrlPril <- ksdfmw <- ksdwrt <- kfioCompleteIO <- kfioWaitIO <- kfioRequestPriv <- kfioRequest <- ksfd_kfioRequest <- ksfd_osmio <- ksfd_io <- ksfdread <- kcfrbd1 <- kcbzib <- kcbgcur <- kturRollbackToSavepoint <- ktcrsp1 <- ksures <- ksuxds <- kssdel <- kssdch <- ksudlp <- opidcl <- opidrv <- sou2o <- opimai_real <- ssthrdmain <- main SUPPORTING INFORMATION: ----------------------- Customer’s Management name: Al Fischer Customer's Management 24x7 contact number: +1-616-648-6244 Customer’s Management email: al.fischer@amway.com Primary Customer Email address: eric.lai Secondary Contact Name: George Zhang Secondary Contact Email: (EMAIL ADDRESS) george.zhang@alticor.com 24 HOUR CONTACT INFORMATION FOR P1 BUGS: ---------------------------------------- DIAL-IN INFORMATION: -------------------- IMPACT DATE: ------------ " system at risk of crashing as alert logging is filling up; causing forms to hang at Call Center" <strong>*** 12/22/10 03:57 am ***</strong> <strong>*** 12/22/10 04:20 am ***</strong> <strong>*** 12/22/10 04:21 am ***</strong> <strong>*** 12/22/10 04:21 am *** (CHG: Sta->16)</strong> <strong>*** 12/22/10 04:33 am ***</strong> <strong>*** 12/22/10 05:35 am ***</strong> <strong>*** 12/22/10 06:08 am ***</strong> <strong>*** 12/22/10 06:09 am ***</strong> <strong>*** 12/22/10 06:10 am ***</strong> <strong>*** 12/22/10 08:06 am ***</strong> <strong>*** 12/22/10 11:25 am *** </strong> <strong>*** 12/22/10 11:25 am ***</strong> <strong>*** 12/22/10 01:47 pm *** (CHG: Sta->10)</strong> <strong>*** 12/22/10 01:47 pm ***</strong> <strong>*** 12/22/10 07:46 pm ***</strong> <strong>*** 12/22/10 07:58 pm ***</strong> File versions form GI & RDBMS homes. Below is the info from GI_HOME. [usax02w] $ ar -t -v -X32_64 $GI_HOME/lib/libserver11.a kfd.o rw-rw-rw- 10000/1026 393236 Nov 15 13:29 2010 kfd.o [usax02w] $ ar -t -v -X32_64 $GI_HOME/lib/libserver11.a kfdp.o rw-rw-rw- 10000/1026 271741 Nov 15 13:29 2010 kfdp.o [usax02w] $ ar -t -v -X32_64 $GI_HOME/lib/libserver11.a kfkio.o rw-rw-rw- 10000/1026 103575 Nov 15 13:29 2010 kfkio.o [usax02w] $ ar -t -v -X32_64 $GI_HOME/lib/libserver11.a kfksubs.o rw-rw-rw- 10000/1026 166215 Nov 15 13:29 2010 kfksubs.o Below is the info from RDBMS_HOME [usax02w] $ echo $ORACLE_HOME /u01/apps/oracle/product/11.2.0/db_1 [usax02w] $ ar -t -v -X32_64 $ORACLE_HOME/lib/libserver11.a kfd.o rw-rw-rw- 10000/1026 393236 Nov 15 13:29 2010 kfd.o [usax02w] $ ar -t -v -X32_64 $ORACLE_HOME/lib/libserver11.a kfdp.o rw-rw-rw- 10000/1026 271741 Nov 15 13:29 2010 kfdp.o [usax02w] $ ar -t -v -X32_64 $ORACLE_HOME/lib/libserver11.a kfkio.o rw-rw-rw- 10000/1026 103575 Nov 15 13:29 2010 kfkio.o [usax02w] $ ar -t -v -X32_64 $ORACLE_HOME/lib/libserver11.a kfksubs.o rw-rw-rw- 10000/1026 166215 Nov 15 13:29 2010 kfksubs.o Regards, Prathap <strong>*** 12/22/10 08:01 pm *** (CHG: Sta->16)</strong> <strong>*** 12/22/10 08:25 pm ***</strong> <strong>*** 12/23/10 01:48 am ***</strong> <strong>*** 12/23/10 02:46 am ***</strong> <strong>*** 12/23/10 06:25 am *** (CHG: Sta->11)</strong> <strong>*** 12/23/10 06:25 am ***</strong> <strong>*** 12/23/10 06:26 am *** </strong> <strong>*** 12/23/10 06:26 am ***</strong> <strong>*** 12/24/10 01:43 am *** </strong> <strong>*** 12/24/10 01:43 am ***</strong> <strong>*** 12/27/10 11:33 am ***</strong> <strong>*** 12/27/10 11:45 am ***</strong> <strong>*** 12/27/10 11:51 am ***</strong> <strong>*** 12/27/10 12:22 pm *** ESCALATED</strong> <strong>*** 12/27/10 12:22 pm ***</strong> <strong>*** 12/27/10 12:29 pm ***</strong> <strong>*** 12/28/10 12:42 am *** (CHG: Sta->30)</strong> <strong>*** 12/28/10 12:42 am ***</strong> <strong>*** 12/28/10 05:00 am *** (CHG: Sta->16)</strong> <strong>*** 12/28/10 05:00 am ***</strong> <strong>*** 12/28/10 05:08 am *** (CHG: Sta->11)</strong> <strong>*** 12/28/10 09:37 am ***</strong> <strong>*** 12/29/10 02:51 am ***</strong> <strong>*** 12/31/10 03:05 am ***</strong> <strong>*** 01/02/11 08:28 pm ***</strong> <strong>*** 01/04/11 01:43 am *** (CHG: Sta->30)</strong> <strong>*** 01/04/11 01:43 am ***</strong> <strong>*** 01/04/11 01:54 am ***</strong> <strong>*** 01/04/11 04:50 am *** (CHG: Sta->11)</strong> <strong>*** 01/04/11 04:50 am ***</strong> <strong>*** 01/05/11 01:26 am *** (CHG: Sta->30)</strong> <strong>*** 01/05/11 01:26 am ***</strong> <strong>*** 01/10/11 10:46 am ***</strong> <strong>*** 01/10/11 10:46 am *** (CHG: Sta->11)</strong> <strong>*** 01/11/11 03:14 am ***</strong> <strong>*** 01/13/11 11:32 pm ***</strong> RELEASE NOTES: ]] kfk SO is deleted, while there are still allocated sessions. REDISCOVERY INFORMATION: The following error, even with fix 10051315: WARNING: IO Failed. group:1 disk(number.incarnation):5.0xe0d14bb7 disk_path:/dev/ASM_1457_4 AU:75811 disk_offset(bytes):79494299648 io_size:8192 operation:Read type:synchronous result:I/O error process_id:2338940 subsys:System iop:0x110939310 bufp:0x70000016f2ec000 osderr:0x434c5344 osderr1:0x0 WORKAROUND: None <strong>*** 01/13/11 11:44 pm *** </strong> <strong>*** 01/13/11 11:44 pm *** </strong> <strong>*** 01/13/11 11:44 pm *** (CHG: Sta->80)</strong> <strong>*** 01/16/11 11:05 pm ***</strong> <strong>*** 01/16/11 11:17 pm ***</strong> <strong>*** 01/16/11 11:36 pm ***</strong> <strong>*** 01/17/11 12:01 am ***</strong> <strong>*** 01/17/11 07:09 am ***</strong> <strong>*** 01/17/11 07:11 am ***</strong> <strong>*** 01/17/11 09:25 am ***</strong> <strong>*** 01/17/11 10:16 am ***</strong> <strong>*** 01/17/11 11:14 pm ***</strong> <strong>*** 01/18/11 05:06 am ***</strong> <strong>*** 01/18/11 11:47 am ***</strong> <strong>*** 01/18/11 11:52 pm ***</strong> <strong>*** 01/19/11 02:05 am ***</strong> <strong>*** 01/19/11 05:39 am ***</strong> <strong>*** 01/19/11 05:45 am ***</strong> <strong>*** 01/19/11 07:43 am ***</strong> <strong>*** 01/19/11 08:44 am ***</strong> <strong>*** 01/19/11 06:12 pm ***</strong> <strong>*** 01/19/11 06:14 pm ***</strong> <strong>*** 01/19/11 10:53 pm ***</strong> <strong>*** 01/20/11 12:11 am ***</strong> <strong>*** 01/20/11 04:04 am ***</strong> <strong>*** 01/20/11 06:11 am ***</strong> <strong>*** 01/20/11 06:59 am ***</strong> <strong>*** 01/20/11 09:13 am ***</strong> <strong>*** 01/20/11 10:44 am ***</strong> <strong>*** 01/20/11 10:44 am ***</strong> <strong>*** 01/20/11 11:00 am ***</strong> <strong>*** 01/20/11 11:38 am ***</strong> <strong>*** 01/20/11 04:58 pm ***</strong> <strong>*** 01/21/11 04:05 am ***</strong> <strong>*** 01/24/11 11:33 am ***</strong> <strong>*** 01/25/11 02:17 am ***</strong> <strong>*** 01/27/11 02:58 am ***</strong> <strong>*** 01/27/11 03:16 am ***</strong> <strong>*** 01/27/11 03:37 am ***</strong> <strong>*** 01/27/11 03:49 am ***</strong> <strong>*** 02/02/11 04:37 am ***</strong> <strong>*** 02/04/11 08:25 pm ***</strong> <strong>*** 02/05/11 02:46 am ***</strong> <strong>*** 02/05/11 02:58 am ***</strong> <strong>*** 02/05/11 02:59 am ***</strong> <strong>*** 02/05/11 02:29 pm ***</strong> <strong>*** 02/05/11 07:19 pm ***</strong> <strong>*** 02/05/11 09:37 pm ***</strong> <strong>*** 02/07/11 01:37 am ***</strong> <strong>*** 02/07/11 06:14 am ***</strong> <strong>*** 02/07/11 12:35 pm ***</strong> <strong>*** 02/07/11 06:46 pm ***</strong> <strong>*** 02/07/11 08:33 pm ***</strong> <strong>*** 02/08/11 01:52 pm ***</strong> <strong>*** 02/08/11 02:42 pm ***</strong> <strong>*** 02/08/11 10:32 pm ***</strong> <strong>*** 02/09/11 11:51 pm ***</strong> <strong>*** 02/10/11 08:56 am ***</strong> <strong>*** 02/10/11 08:59 am ***</strong> <strong>*** 02/10/11 09:30 am ***</strong> <strong>*** 02/11/11 11:52 pm ***</strong> <strong>*** 02/12/11 05:10 pm ***</strong> <strong>*** 02/15/11 02:55 am ***</strong> <strong>*** 02/15/11 10:13 am ***</strong> <strong>*** 02/16/11 01:07 am ***</strong> <strong>*** 02/16/11 06:34 am ***</strong> <strong>*** 02/18/11 01:39 am ***</strong> <strong>*** 02/18/11 01:40 am ***</strong> <strong>*** 02/24/11 07:20 am ***</strong> <strong>*** 02/24/11 07:35 am ***</strong> <strong>*** 02/25/11 12:34 am ***</strong> <strong>*** 03/02/11 07:59 am ***</strong> <strong>*** 03/02/11 08:25 am ***</strong> <strong>*** 03/03/11 01:22 am ***</strong> <strong>*** 03/03/11 03:34 pm ***</strong> <strong>*** 03/07/11 11:54 am ***</strong> <strong>*** 03/08/11 08:53 pm ***</strong> <strong>*** 03/09/11 10:44 pm ***</strong> <strong>*** 04/20/11 01:17 pm ***</strong> <strong>*** 04/21/11 09:34 am ***</strong> <strong>*** 04/21/11 01:46 pm ***</strong> <strong>*** 04/22/11 03:47 pm ***</strong> <strong>*** 04/29/11 12:33 pm ***</strong> <strong>*** 04/29/11 01:21 pm ***</strong> <strong>*** 05/02/11 07:53 am ***</strong> <strong>*** 05/03/11 01:12 am ***</strong> <strong>*** 05/03/11 01:37 am ***</strong> <strong>*** 05/03/11 02:11 am ***</strong> <strong>*** 05/11/11 03:00 am ***</strong> <strong>*** 05/11/11 03:44 am ***</strong> <strong>*** 05/16/11 08:07 am ***</strong> <strong>*** 05/17/11 11:31 am ***</strong> <strong>*** 05/17/11 11:34 am ***</strong> <strong>*** 05/17/11 03:14 pm ***</strong> <strong>*** 05/17/11 03:16 pm ***</strong> <strong>*** 05/18/11 06:00 am ***</strong> <strong>*** 05/18/11 06:11 am ***</strong> <strong>*** 05/18/11 08:46 am ***</strong> <strong>*** 06/09/11 12:44 pm ***</strong> <strong>*** 06/10/11 10:21 am ***</strong> <strong>*** 06/10/11 10:21 am ***</strong> <strong>*** 06/11/11 04:44 am ***</strong> <strong>*** 06/14/11 10:14 pm ***</strong> <strong>*** 06/17/11 12:33 pm ***</strong> <strong>*** 07/04/11 01:09 pm ***</strong> <strong>*** 07/06/11 04:03 pm ***</strong> <strong>*** 07/06/11 04:56 pm ***</strong> <strong>*** 07/08/11 11:47 am ***</strong> <strong>*** 07/08/11 12:16 pm ***</strong> <strong>*** 07/12/11 07:28 am ***</strong> <strong>*** 07/14/11 07:58 pm *** </strong> <strong>*** 07/17/11 05:29 am ***</strong> <strong>*** 07/17/11 05:30 am ***</strong> <strong>*** 07/18/11 03:23 pm ***</strong> <strong>*** 07/26/11 03:20 pm ***</strong> <strong>*** 07/26/11 03:23 pm ***</strong> <strong>*** 07/27/11 03:13 am ***</strong> <strong>*** 07/27/11 03:15 am ***</strong> <strong>*** 07/27/11 07:33 am ***</strong> <strong>*** 08/02/11 01:34 pm ***</strong> <strong>*** 08/03/11 01:03 am *** </strong> <strong>*** 08/03/11 01:03 am ***</strong> <strong>*** 08/03/11 01:15 am *** </strong> <strong>*** 08/03/11 01:15 am ***</strong> <strong>*** 08/05/11 08:00 am ***</strong> <strong>*** 08/05/11 08:11 am ***</strong> <strong>*** 08/05/11 10:42 am ***</strong> <strong>*** 08/11/11 01:22 am ***</strong> <strong>*** 08/12/11 04:00 am ***</strong> <strong>*** 08/12/11 10:03 am ***</strong> <strong>*** 08/18/11 12:46 pm ***</strong> <strong>*** 08/22/11 12:14 pm ***</strong> <strong>*** 09/07/11 04:49 am ***</strong> <strong>*** 09/09/11 02:55 pm ***</strong> <strong>*** 09/14/11 02:40 pm ***</strong> <strong>*** 10/14/11 02:15 am ***</strong> <strong>*** 10/14/11 02:15 am *** ESCALATION -> CLOSED</strong> <strong>*** 10/14/11 02:15 am *** (CHG: Sta->90)</strong> <strong>*** 10/14/11 02:21 am *** </strong> <strong>*** 10/14/11 02:21 am ***</strong> <strong>*** 10/14/11 09:56 am ***</strong> <strong>*** 11/01/11 01:55 am ***</strong> <strong>*** 11/01/11 10:49 am ***</strong> <strong>*** 11/01/11 10:49 am ***</strong> <strong>*** 11/27/11 01:15 am ***</strong> <strong>*** 12/01/11 09:11 am ***</strong> <strong>*** 01/17/12 03:29 pm ***</strong> <strong>*** 01/23/12 08:26 pm ***</strong> <strong>*** 01/23/12 08:26 pm ***</strong> <strong>*** 03/14/12 01:07 am ***</strong> <strong>*** 03/18/12 11:22 pm ***</strong> <strong>*** 03/22/12 12:44 am ***</strong> <strong>*** 04/02/12 06:10 am ***</strong> <strong>*** 04/24/12 10:45 am ***</strong> <strong>*** 01/26/13 08:03 am ***</strong> <strong>*** 01/31/13 07:35 am ***</strong> <strong>*** 02/24/13 11:27 pm ***</strong> <strong>*** 04/16/13 02:14 am ***</strong> <strong>*** 04/19/13 07:23 am ***</strong> <strong>*** 05/12/13 09:12 pm ***</strong> <strong>*** 05/20/13 06:28 am ***</strong> <strong>*** 06/25/13 01:16 am ***</strong> <strong>*** 07/08/13 09:41 pm ***</strong> <strong>*** 07/09/13 09:44 pm ***</strong> <strong>*** 07/09/13 10:24 pm ***</strong> <strong>*** 07/17/13 03:02 am ***</strong> <strong>*** 07/18/13 02:35 am ***</strong> <strong>*** 08/12/13 03:54 am ***</strong> <strong>*** 08/20/13 12:21 am ***</strong> <strong>*** 09/30/13 12:26 pm ***</strong> <strong>*** 10/23/13 05:08 pm ***</strong> <strong>*** 10/29/13 08:22 am ***</strong> <strong>*** 10/29/13 09:56 am ***</strong> <strong>*** 10/29/13 09:56 am ***</strong> <strong>*** 12/18/13 03:38 am ***</strong> <strong>*** 01/23/14 09:24 pm ***</strong> <strong>*** 02/11/14 09:58 am ***</strong> <strong>*** 02/24/14 03:11 am ***</strong> <strong>*** 02/24/14 06:02 am ***</strong> <strong>*** 02/24/14 12:34 pm ***</strong> <strong>*** 02/24/14 03:58 pm ***</strong> <strong>*** 02/25/14 02:28 am ***</strong> <strong>*** 03/18/14 04:34 am ***</strong> <strong>*** 03/18/14 04:55 am ***</strong> <strong>*** 03/18/14 05:09 am ***</strong> <strong>*** 03/18/14 10:37 pm ***</strong> <strong>*** 03/19/14 12:39 am ***</strong>

데이터베이스 최적화에서 쿼리 요구 사항에 따라 인덱싱 전략을 선택해야합니다. 1. 쿼리에 여러 열이 포함되고 조건 순서가 수정되면 복합 인덱스를 사용하십시오. 2. 쿼리에 여러 열이 포함되어 있지만 조건 순서가 고정되지 않은 경우 여러 단일 열 인덱스를 사용하십시오. 복합 인덱스는 다중 열 쿼리를 최적화하는 데 적합한 반면 단일 열 인덱스는 단일 열 쿼리에 적합합니다.

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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