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How does MySQL INNODB Engine lock work? Let's test it. Mysqlgt; SELECTVERSION (); + ----------- + | VERSION () | + ----------- + | 5.5 How does MySQL INNODB Engine lock work? Let's test it. Mysqlgt; select version (); + ----------- + | VERSION () | +

I am used to installing MySQL in binary format. Today I am eager to install an RPM package for MySQL to play. I did not expect that I encountered some problems. I will share with you the problems I encountered first. I am used to installing MySQL

Generally, the Oracle database locks the user after 10 failed attempts by default. 1. view the value of FAILED_LOGIN_ATTEMPTS select * fromdba_profiles; 2. modify it to 30 times. Generally, the Oracle database locks the user after 10 failed attempts

Sometimes the standby database lags behind the primary database for a long time, and the archive log of the primary database does not exist. How can we eliminate the log interval at this time? Many people choose to recreate the standby database,

MySQL5.6 adds a method that does not need to set the log_bin file and log location. Before that, we need to view the master machine information (showmasterstatus), and then set MySQL5.6 adds a method that does not need to set the log_bin file and

Operating System: rhel5.4x86, database: Oracle11gR2. Experiment Description: This experiment aims to show that the B-Tree index performance is better than the BitMap index. Read from consistency Operating System: rhel 5.4x86, database: Oracle 11g R2,

**************************************** * *********** Upgrade MySQL5.6.19 to 5.6.21 *********************** ***************** /*************************************** * ************ Upgrade MySQL to 5.6.21 ********************* *******************

A previous database was used for testing (department A). Last night, another test department (Department B) came to test the program. Two users were created on the database and imported data, A previous database was used for testing (department A).

Setting the SQL _trace parameter to true will track the entire instance, including all processes: User processes and background processes, which may cause serious performance problems. Be cautious in the production environment. Setting the SQL

In DataGuard configuration, sometimes we need to use RMAN to automatically delete archive logs that have been applied to the slave database from FRA. When the database meets the following conditions, the archived logs under FRA will be In DataGuard

When SQL plus is used to execute an SQL statement, a prompt such as "ldquo" and "XX rows of rdquo" can be returned in a SELECT statement, but this prompt is not found when a library is opened recently. When SQL plus is used to execute an SQL

The previous article Sqoop1.4.4 import incremental data from Oracle10g to Hive0.13.1 and update the master table in Hive describes the principle of incremental update of Hive tables and Sq The previous article Sqoop1.4.4 import incremental data from

CREATEGLOBALTEMPORARYTABLETABLENAME (COL1VARCHAR2 (10), COL2NUMBER) ONCOMMITPRESERVE (DELETE) ROWS; -- O Create global temporary table tablename (COL1 VARCHAR2 (10), COL2 NUMBER) on commit preserve (DELETE) ROWS; -- O Create global temporary

The original Oracle database server uses rman to back up the entire database, and then restores the same database on the remote server. The original Oracle database server uses rman to back up the entire database, and then restores the same database

Need to disable AWR? Such a good stuff. By default, AWR is usable and requires a certain amount of sysaux tablespace. However, it involves debugging packages related to AWR (li Need to disable AWR? Such a good stuff. By default, AWR is usable and

The company set up a slave uard. At the beginning, it did not pay attention to the management of archiving logs in the slave database. After the system was running for a while, it was found that the space of the slave database was cracked up by

MySQL supports constant transfer for expression simplification. For example: CREATETABLE 't1' ('id1' int (11) NOTNULLDEFAULT MySQL supports constant transfer for expression simplification. For example, create table 't1' ('id1' int (11) NOT NULL

As shown in the following example, recompilation of objects in the production database will lead to librarycachelock, so we should avoid compiling objects during business peaks. If From the example below, we can see that re-Compilation of objects in

As long as the database is in the OPEN state, other tablespaces except the SYSTEM tablespace can be set to online or offline. The reason why the SYSTEM tablespace cannot be set to As long as the database is in the OPEN state, other tablespaces

Today, my colleague reflected a problem, a test database modified the password, and changed the password used by the application, still appear after a while the account is locked, reported ORA-28000: theaccount Today, my colleague reported a problem,