搜索
首页数据库mysql教程数据文件从系统文件迁移到asm的操作专栏

数据文件从系统文件迁移到asm的操作专栏

PHPz
PHPz
Jun 07, 2016 pm 03:56 PM
oracle

select file_name ,tablespace_name from dba_data_files ;

FILE_NAME                      TABLESPACE_NAME
--------------------------------------------- ------------------------------
+DATA/rac/datafile/system.259.926647219       SYSTEM
+DATA/rac/datafile/sysaux.260.926647323       SYSAUX
+DATA/rac/datafile/undotbs1.261.926647405     UNDOTBS1
+DATA/rac/datafile/undotbs2.263.926647467     UNDOTBS2
+DATA/rac/datafile/users.264.926647499          USERS
+DATA/rac/datafile/admin_tbs.274.927927081    ADMIN_TBS
+DATA/rac/datafile/admin_tb2.275.927927171    ADMIN_TB2
+DATA/rac/datafile/tbs_low_freq.276.927939255 TBS_LOW_FREQ
/oracle/app/oracle/11.2/db_1/dbs/q1_orders    Q1_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/q2_orders    Q2_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/q3_orders    Q3_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/q4_orders    Q4_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/2006_orders  2006_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/2005_orders  2005_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/2004_orders  2004_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/old_orders   OLD_ORDERS
/oracle/app/oracle/11.2/db_1/dbs/cc_this_mont CC_THIS_MONTH

数据文件都节点1本地。

案例重演：
sys@RAC> show parameter db_create_file_dest

NAME                     TYPE     VALUE
------------------------------------ ----------- ------------------------------
db_create_file_dest             string     +DATA

采用了omf管理
sys@RAC> create tablespace qn datafile size 20m ;

Tablespace created.

sys@RAC> select file_name ,tablespace_name from dba_data_files ;

FILE_NAME                      TABLESPACE_NAME
--------------------------------------------- ------------------------------
.........
+DATA/rac/datafile/qn.277.928807173          QN
此时发现数据文件qn建在ASM存储上

sys@RAC> create tablespace qn2 datafile 'qn2' size 20m ;
Tablespace created.
sys@RAC> select file_name ,tablespace_name from dba_data_files ;

FILE_NAME                      TABLESPACE_NAME
--------------------------------------------- ------------------------------
/oracle/app/oracle/11.2/db_1/dbs/cc_prev_12   CC_PREV_12MTH
/oracle/app/oracle/11.2/db_1/dbs/cc_old_tran  CC_OLD_TRAN
+DATA/rac/datafile/qn.277.928807173          QN
/oracle/app/oracle/11.2/db_1/dbs/qn2          QN2
此时发现数据文件qn2建在系统文件上,这样会出问题的，其节点报错。

那么如何把这个数据库的系统文件迁移到ASM上呢？

在线迁移数据文件至ASM上：

1. offline数据文件
   select file_name ,tablespace_name from dba_data_files  where tablespace_name in ('Q1_ORDERS','Q2_ORDERS','Q3_ORDERS','Q4_ORDERS','2006_ORDERS','2005_ORDERS','2004_ORDERS','OLD_ORDERS','CC_THIS_MONTH','CC_PREV_MONTH','CC_PREV_12MTH','QN2' ) ;
   FILE_NAME                             TABLESPACE_NAME
   ------------------------------------------------------------ ------------------------------
   /oracle/app/oracle/11.2/db_1/dbs/q1_orders             Q1_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/q2_orders             Q2_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/q3_orders             Q3_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/q4_orders             Q4_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/2006_orders             2006_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/2005_orders             2005_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/2004_orders             2004_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/old_orders             OLD_ORDERS
   /oracle/app/oracle/11.2/db_1/dbs/cc_this_month             CC_THIS_MONTH
   /oracle/app/oracle/11.2/db_1/dbs/cc_prev_month             CC_PREV_MONTH
   /oracle/app/oracle/11.2/db_1/dbs/cc_prev_12             CC_PREV_12MTH
   /oracle/app/oracle/11.2/db_1/dbs/qn2                 QN2

2. rman copy
   alter tablespace Q1_ORDERS offline ;

   backup as copy datafile '/oracle/app/oracle/11.2/db_1/dbs/q1_orders'  format '+DATA';
   or
   copy datafile  '/oracle/app/oracle/11.2/db_1/dbs/q1_orders' to '+DATA';


  RMAN>  copy datafile  '/oracle/app/oracle/11.2/db_1/dbs/q1_orders' to '+DATA';

  Starting backup at 2016-11-25 02:55:42
  using target database control file instead of recovery catalog
  allocated channel: ORA_DISK_1
  channel ORA_DISK_1: SID=28 instance=rac1 device type=DISK
  channel ORA_DISK_1: starting datafile copy
  input datafile file number=00009 name=/oracle/app/oracle/11.2/db_1/dbs/q1_orders
  output file name=+DATA/rac/datafile/q1_orders.278.928810547 tag=TAG20161125T025546 RECID=1 STAMP=928810550
  channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
  Finished backup at 2016-11-25 02:55:50

3. rename
  alter database rename file 'D:\NSOADP\SYSTEM01.DBF' to '+ORADATA/nsoa/datafile/system.260.877082571';
  or
  switch datafile 37 to copy;

  RMAN> switch datafile '/oracle/app/oracle/11.2/db_1/dbs/q1_orders' to copy ;
  datafile 9 switched to datafile copy "+DATA/rac/datafile/q1_orders.278.928810547"


4. recover
    recover datafile '+DATA/rac/datafile/q1_orders.278.928810547';

5. online
  alter tablespace Q1_ORDERS online

  sys@RAC> select file_name ,tablespace_name from dba_data_files  where tablespace_name in ('Q1_ORDERS')
    2  /

  FILE_NAME                             TABLESPACE_NAME
  ------------------------------------------------------------ ------------------------------
  +DATA/rac/datafile/q1_orders.278.928810547             Q1_ORDERS

快速恢复:
  sys@RAC> select file_name ,tablespace_name from dba_data_files  where tablespace_name in ('Q2_ORDERS','Q3_ORDERS','Q4_ORDERS','2006_ORDERS','2005_ORDERS','2004_ORDERS','OLD_ORDERS','CC_THIS_MONTH','CC_PREV_MONTH','CC_PREV_12MTH','QN2' ) ;

  FILE_NAME                             TABLESPACE_NAME
  ------------------------------------------------------------ ------------------------------
  /oracle/app/oracle/11.2/db_1/dbs/q2_orders             Q2_ORDERS
  /oracle/app/oracle/11.2/db_1/dbs/q3_orders             Q3_ORDERS
  /oracle/app/oracle/11.2/db_1/dbs/q4_orders             Q4_ORDERS
  /oracle/app/oracle/11.2/db_1/dbs/2006_orders             2006_ORDERS
  /oracle/app/oracle/11.2/db_1/dbs/2005_orders             2005_ORDERS
  /oracle/app/oracle/11.2/db_1/dbs/2004_orders             2004_ORDERS
  /oracle/app/oracle/11.2/db_1/dbs/old_orders             OLD_ORDERS
  /oracle/app/oracle/11.2/db_1/dbs/cc_this_month             CC_THIS_MONTH
  /oracle/app/oracle/11.2/db_1/dbs/cc_prev_month             CC_PREV_MONTH
  /oracle/app/oracle/11.2/db_1/dbs/cc_prev_12             CC_PREV_12MTH
  /oracle/app/oracle/11.2/db_1/dbs/qn2                 QN2

sys@RAC>    select 'alter tablespace '|| tablespace_name||' offline;'  from dba_data_files  where tablespace_name in ('Q2_ORDERS','Q3_ORDERS','Q4_ORDERS','2006_ORDERS','2005_ORDERS','2004_ORDERS','OLD_ORDERS','CC_THIS_MONTH','CC_PREV_MONTH','CC_PREV_12MTH','QN2' ) ;

'ALTERTABLESPACE'||TABLESPACE_NAME||'OFFLINE;'
--------------------------------------------------------
alter tablespace Q2_ORDERS offline;
alter tablespace Q3_ORDERS offline;
alter tablespace Q4_ORDERS offline;
alter tablespace 2006_ORDERS offline;
alter tablespace 2005_ORDERS offline;
alter tablespace 2004_ORDERS offline;
alter tablespace OLD_ORDERS offline;
alter tablespace CC_THIS_MONTH offline;
alter tablespace CC_PREV_MONTH offline;
alter tablespace CC_PREV_12MTH offline;
alter tablespace QN2 offline;

sys@RAC> sys@RAC> alter tablespace Q2_ORDERS offline;
alter tablespace Q3_ORDERS offline;
alter tablespace Q4_ORDERS offline;
alter tablespace 2006_ORDERS offline;
alter tablespace 2005_ORDERS offline;
alter tablespace 2004_ORDERS offline;
alter tablespace OLD_ORDERS offline;
alter tablespace CC_THIS_MONTH offline;
alter tablespace CC_PREV_MONTH offline;
alter tablespace CC_PREV_12MTH offline;
alter tablespace QN2 offline;

sys@RAC> alter tablespace "2006_ORDERS" offline
                 *
ERROR at line 1:
ORA-02140: invalid tablespace name

sys@RAC> alter tablespace 2005_ORDERS offline
                 *
ERROR at line 1:
ORA-02140: invalid tablespace name

sys@RAC> alter tablespace 2004_ORDERS offline
                 *
ERROR at line 1:
ORA-02140: invalid tablespace name

alter tablespace "2004_ORDERS" offline;
alter tablespace "2005_ORDERS" offline;
alter tablespace "2006_ORDERS" offline;

 select 'copy datafile '''||file_name||''' to ''+DATA'';'  from dba_data_files  where tablespace_name in ('Q2_ORDERS','Q3_ORDERS','Q4_ORDERS','2006_ORDERS','2005_ORDERS','2004_ORDERS','OLD_ORDERS','CC_THIS_MONTH','CC_PREV_MONTH','CC_PREV_12MTH','QN2' ) ;

'COPYDATAFILE'''||FILE_NAME||'''TO''+DATA'';'
----------------------------------------------------------------------------------------------------------------------------------------------------------
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/q2_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/q3_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/q4_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/2006_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/2005_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/2004_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/old_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_this_month' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_month' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_12' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/qn2' to '+DATA';

RMAN> copy datafile '/oracle/app/oracle/11.2/db_1/dbs/q2_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/q3_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/q4_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1
/dbs/2006_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/2005_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/2004_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/old_orders' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_this_month' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_month' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_12' to '+DATA';
copy datafile '/oracle/app/oracle/11.2/db_1/dbs/qn2' to '+DATA';Starting backup at 2016-11-25 03:20:57
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00010 name=/oracle/app/oracle/11.2/db_1/dbs/q2_orders
output file name=+DATA/rac/datafile/q2_orders.279.928812061 tag=TAG20161125T032059 RECID=3 STAMP=928812062
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 2016-11-25 03:21:02

RMAN>
Starting backup at 2016-11-25 03:21:08
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00011 name=/oracle/app/oracle/11.2/db_1/dbs/q3_orders
output file name=+DATA/rac/datafile/q3_orders.280.928812071 tag=TAG20161125T032109 RECID=4 STAMP=928812073
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:07
Finished backup at 2016-11-25 03:21:17

RMAN>
Starting backup at 2016-11-25 03:21:22
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00012 name=/oracle/app/oracle/11.2/db_1/dbs/q4_orders
output file name=+DATA/rac/datafile/q4_orders.281.928812085 tag=TAG20161125T032124 RECID=5 STAMP=928812088
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 2016-11-25 03:21:28

RMAN>
Starting backup at 2016-11-25 03:21:33
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00013 name=/oracle/app/oracle/11.2/db_1/dbs/2006_orders
output file name=+DATA/rac/datafile/2006_orders.282.928812095 tag=TAG20161125T032134 RECID=6 STAMP=928812099
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:07
Finished backup at 2016-11-25 03:21:42

RMAN>
Starting backup at 2016-11-25 03:21:46
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00014 name=/oracle/app/oracle/11.2/db_1/dbs/2005_orders
output file name=+DATA/rac/datafile/2005_orders.283.928812109 tag=TAG20161125T032148 RECID=7 STAMP=928812112
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:07
Finished backup at 2016-11-25 03:21:56

RMAN>
Starting backup at 2016-11-25 03:22:00
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00015 name=/oracle/app/oracle/11.2/db_1/dbs/2004_orders
output file name=+DATA/rac/datafile/2004_orders.284.928812123 tag=TAG20161125T032202 RECID=8 STAMP=928812126
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:07
Finished backup at 2016-11-25 03:22:10

RMAN>
Starting backup at 2016-11-25 03:22:14
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00016 name=/oracle/app/oracle/11.2/db_1/dbs/old_orders
output file name=+DATA/rac/datafile/old_orders.285.928812137 tag=TAG20161125T032216 RECID=9 STAMP=928812141
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:07
Finished backup at 2016-11-25 03:22:24

RMAN>
Starting backup at 2016-11-25 03:22:29
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00017 name=/oracle/app/oracle/11.2/db_1/dbs/cc_this_month
output file name=+DATA/rac/datafile/cc_this_month.286.928812151 tag=TAG20161125T032231 RECID=10 STAMP=928812154
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 2016-11-25 03:22:34

RMAN>
Starting backup at 2016-11-25 03:22:45
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00018 name=/oracle/app/oracle/11.2/db_1/dbs/cc_prev_month
output file name=+DATA/rac/datafile/cc_prev_month.287.928812167 tag=TAG20161125T032246 RECID=11 STAMP=928812167
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01
Finished backup at 2016-11-25 03:22:47

RMAN>
Starting backup at 2016-11-25 03:22:52
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00019 name=/oracle/app/oracle/11.2/db_1/dbs/cc_prev_12
output file name=+DATA/rac/datafile/cc_prev_12mth.288.928812175 tag=TAG20161125T032253 RECID=12 STAMP=928812175
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 2016-11-25 03:22:57

Starting backup at 2016-11-25 03:26:09

RMAN>
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00022 name=/oracle/app/oracle/11.2/db_1/dbs/qn2
output file name=+DATA/rac/datafile/qn2.289.928812371 tag=TAG20161125T032611 RECID=13 STAMP=928812376
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:07
Finished backup at 2016-11-25 03:26:18


 sys@RAC> select 'switch  datafile '''||file_name||''' to copy;'  from dba_data_files  where tablespace_name in ('Q2_ORDERS','Q3_ORDERS','Q4_ORDERS','2006_ORDERS','2005_ORDERS','2004_ORDERS','OLD_ORDERS','CC_THIS_MONTH','CC_PREV_MONTH','CC_PREV_12MTH','QN2' ) ;

'SWITCHDATAFILE'''||FILE_NAME||'''TOCOPY;'
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/q2_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/q3_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/q4_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/2006_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/2005_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/2004_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/old_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_this_month' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_month' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_12' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/qn2' to copy;

RMAN> switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/q2_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/q3_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/q4_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/
dbs/2006_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/2005_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/2004_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/old_orders' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_this_month' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_month' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/cc_prev_12' to copy;
switch    datafile '/oracle/app/oracle/11.2/db_1/dbs/qn2' to copy;
datafile 10 switched to datafile copy "+DATA/rac/datafile/q2_orders.279.928812061"
RMAN>
datafile 11 switched to datafile copy "+DATA/rac/datafile/q3_orders.280.928812071"
RMAN>
datafile 12 switched to datafile copy "+DATA/rac/datafile/q4_orders.281.928812085"
RMAN>
datafile 13 switched to datafile copy "+DATA/rac/datafile/2006_orders.282.928812095"
RMAN>
datafile 14 switched to datafile copy "+DATA/rac/datafile/2005_orders.283.928812109"
RMAN>
datafile 15 switched to datafile copy "+DATA/rac/datafile/2004_orders.284.928812123"
RMAN>
datafile 16 switched to datafile copy "+DATA/rac/datafile/old_orders.285.928812137"
RMAN>
datafile 17 switched to datafile copy "+DATA/rac/datafile/cc_this_month.286.928812151"
RMAN>
datafile 18 switched to datafile copy "+DATA/rac/datafile/cc_prev_month.287.928812167"
RMAN>
datafile 19 switched to datafile copy "+DATA/rac/datafile/cc_prev_12mth.288.928812175"
RMAN>
datafile 22 switched to datafile copy "+DATA/rac/datafile/qn2.289.928812371"

alter tablespace Q3_ORDERS online;
alter tablespace Q4_ORDERS online;
alter tablespace "2006_ORDERS" online;
alter tablespace "2005_ORDERS" online;
alter tablespace "2004_ORDERS" online;
alter tablespace OLD_ORDERS online;
alter tablespace CC_THIS_MONTH online;
alter tablespace CC_PREV_MONTH online;
alter tablespace CC_PREV_12MTH online;
alter tablespace QN2 online;

sys@RAC>  select file_name ,tablespace_name from dba_data_files  where tablespace_name in ('Q1_ORDERS','Q2_ORDERS','Q3_ORDERS','Q4_ORDERS','2006_ORDERS','2005_ORDERS','2004_ORDERS','OLD_ORDERS','CC_THIS_MONTH','CC_PREV_MONTH','CC_PREV_12MTH','QN2' ) ;
FILE_NAME                             TABLESPACE_NAME
------------------------------------------------------------ ------------------------------
+DATA/rac/datafile/q1_orders.278.928810547             Q1_ORDERS
+DATA/rac/datafile/q2_orders.279.928812061             Q2_ORDERS
+DATA/rac/datafile/q3_orders.280.928812071             Q3_ORDERS
+DATA/rac/datafile/q4_orders.281.928812085             Q4_ORDERS
+DATA/rac/datafile/2006_orders.282.928812095             2006_ORDERS
+DATA/rac/datafile/2005_orders.283.928812109             2005_ORDERS
+DATA/rac/datafile/2004_orders.284.928812123             2004_ORDERS
+DATA/rac/datafile/old_orders.285.928812137             OLD_ORDERS
+DATA/rac/datafile/cc_this_month.286.928812151             CC_THIS_MONTH
+DATA/rac/datafile/cc_prev_month.287.928812167             CC_PREV_MONTH
+DATA/rac/datafile/cc_prev_12mth.288.928812175             CC_PREV_12MTH
+DATA/rac/datafile/qn2.289.928812371                 QN2

至此系统上的数据文件都迁移到asm上。

更多相关教程请访问 MySQL视频教程

声明
本文转载于：CSDN博客。如有侵权，请联系admin@php.cn删除
相关文章
将用户添加到MySQL：完整的教程将用户添加到MySQL：完整的教程May 12, 2025 am 12:14 AM

掌握添加MySQL用户的方法对于数据库管理员和开发者至关重要，因为它确保数据库的安全性和访问控制。1)使用CREATEUSER命令创建新用户，2)通过GRANT命令分配权限，3)使用FLUSHPRIVILEGES确保权限生效，4)定期审计和清理用户账户以维护性能和安全。

掌握mySQL字符串数据类型：varchar vs.文本与char掌握mySQL字符串数据类型：varchar vs.文本与charMay 12, 2025 am 12:12 AM

chosecharforfixed-lengthdata，varcharforvariable-lengthdata，andtextforlargetextfield.1）chariseffity forconsistent-lengthdatalikecodes.2）varcharsuitsvariable-lengthdatalikenames，ballancingflexibilitibility andperformance.3）

MySQL：字符串数据类型和索引：最佳实践MySQL：字符串数据类型和索引：最佳实践May 12, 2025 am 12:11 AM

在MySQL中处理字符串数据类型和索引的最佳实践包括：1)选择合适的字符串类型，如CHAR用于固定长度，VARCHAR用于可变长度，TEXT用于大文本；2)谨慎索引，避免过度索引，针对常用查询创建索引；3)使用前缀索引和全文索引优化长字符串搜索；4)定期监控和优化索引，保持索引小巧高效。通过这些方法，可以在读取和写入性能之间取得平衡，提升数据库效率。

mysql：如何远程添加用户mysql：如何远程添加用户May 12, 2025 am 12:10 AM

ToaddauserremotelytoMySQL,followthesesteps:1)ConnecttoMySQLasroot,2)Createanewuserwithremoteaccess,3)Grantnecessaryprivileges,and4)Flushprivileges.BecautiousofsecurityrisksbylimitingprivilegesandaccesstospecificIPs,ensuringstrongpasswords,andmonitori

MySQL字符串数据类型的最终指南：有效的数据存储MySQL字符串数据类型的最终指南：有效的数据存储May 12, 2025 am 12:05 AM

tostorestringsefliceflicyInmySql，ChooSetherightDataTypeBasedyOrneOrneEds：1）USEcharforFixed-LengthStstringStringStringSlikeCountryCodes.2）UseVarcharforvariable-lengtthslikenames.3）USETEXTCONTENT.3）

mysql blob vs.文本：为大对象选择正确的数据类型mysql blob vs.文本：为大对象选择正确的数据类型May 11, 2025 am 12:13 AM

选择MySQL的BLOB和TEXT数据类型时，BLOB适合存储二进制数据，TEXT适合存储文本数据。1)BLOB适用于图片、音频等二进制数据，2)TEXT适用于文章、评论等文本数据，选择时需考虑数据性质和性能优化。

MySQL：我应该将root用户用于产品吗？MySQL：我应该将root用户用于产品吗？May 11, 2025 am 12:11 AM

No,youshouldnotusetherootuserinMySQLforyourproduct.Instead,createspecificuserswithlimitedprivilegestoenhancesecurityandperformance:1)Createanewuserwithastrongpassword,2)Grantonlynecessarypermissionstothisuser,3)Regularlyreviewandupdateuserpermissions

MySQL字符串数据类型说明了：选择适合您数据的合适类型MySQL字符串数据类型说明了：选择适合您数据的合适类型May 11, 2025 am 12:10 AM

mySqlStringDatatatPessHouldBechoseBeadeDataCharacteristicsAndUsecases：1）USECHARFORFIXED LENGTHSTRINGSTRINGSLIKECOUNTRYCODES.2）USEDES.2）usevarcharforvariable-lengtthstringstringstringstringstringstringstringslikenames.3）usebinaryorvarrinaryorvarinarydatalbonydatalgebgeenfopical.4）

See all articles

热AI工具

Undresser.AI Undress

Undresser.AI Undress

人工智能驱动的应用程序，用于创建逼真的裸体照片

AI Clothes Remover

AI Clothes Remover

用于从照片中去除衣服的在线人工智能工具。

Undress AI Tool

Undress AI Tool

免费脱衣服图片

Clothoff.io

Clothoff.io

AI脱衣机

Video Face Swap

Video Face Swap

使用我们完全免费的人工智能换脸工具轻松在任何视频中换脸！

显示更多

热门文章

<🎜>：种植花园 - 完整的突变指南
3 周前ByDDD
<🎜>：泡泡胶模拟器无穷大 - 如何获取和使用皇家钥匙
3 周前By尊渡假赌尊渡假赌尊渡假赌
如何修复KB5055612无法在Windows 10中安装？
3 周前ByDDD
北端：融合系统，解释
3 周前By尊渡假赌尊渡假赌尊渡假赌
Mandragora：巫婆树的耳语 - 如何解锁抓钩
3 周前By尊渡假赌尊渡假赌尊渡假赌
显示更多

热工具

SecLists

SecLists

SecLists是最终安全测试人员的伙伴。它是一个包含各种类型列表的集合，这些列表在安全评估过程中经常使用，都在一个地方。SecLists通过方便地提供安全测试人员可能需要的所有列表，帮助提高安全测试的效率和生产力。列表类型包括用户名、密码、URL、模糊测试有效载荷、敏感数据模式、Web shell等等。测试人员只需将此存储库拉到新的测试机上，他就可以访问到所需的每种类型的列表。

Dreamweaver Mac版

Dreamweaver Mac版

视觉化网页开发工具

MinGW - 适用于 Windows 的极简 GNU

MinGW - 适用于 Windows 的极简 GNU

这个项目正在迁移到osdn.net/projects/mingw的过程中，你可以继续在那里关注我们。MinGW：GNU编译器集合（GCC）的本地Windows移植版本，可自由分发的导入库和用于构建本地Windows应用程序的头文件；包括对MSVC运行时的扩展，以支持C99功能。MinGW的所有软件都可以在64位Windows平台上运行。

SublimeText3 英文版

SublimeText3 英文版

推荐：为Win版本，支持代码提示！

WebStorm Mac版

WebStorm Mac版

好用的JavaScript开发工具

显示更多

热门话题

Java教程
1665
14
CakePHP 教程
1424
52
Laravel 教程
1322
25
PHP教程
1270
29
C# 教程
1249
24
显示更多