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1. Two solutions to slave SQL running: no Enter the slave server and run: mysql> show slave status\G ....... Relay_Log_File: localhost-relay-bin.000535 Relay_Log_Pos: 21795072 Relay_Master_Log_File: localhost-bin.000094 Slave_IO_Running: Yes Slave_SQL_Running: No Replicate_ ...

1. View the objects in the tablespace SELECT OWNER AS OWNER, SEGMENT_NAME AS SEGMENT_NAME, SEGMENT_TYPE AS SEGMENT_TYPE, SUM (BYTES) / 1024 / 1024 AS SEGMENT_SIZE FROM DBA_SEGMENTS WHERE TABLESPACE_NAME = 'TBS' GROUP BY OWNER, SEGMENT_NAME, SEGMENT_TYPE; 2. move the ordinary ...

MyBatis supports persistent enum type properties. Suppose that there is a column of gender type varchar2(10) in the t Uuser table, which stores two values: MALE or FEMALE. In addition, the User object has a gender attribute of enum type, as follows: public enum Gender { MALE,FEMALE; }   By default, MyBatis uses EnumTypeHandler to han ...

I am not good at writing. If there is something wrong, please point out it generously. Thank you very much. To learn things, we need to integrate knowledge with practice. If we only know the theory but never practice it, we will not have a solid grasp of it. It is estimated that we will forget it in a few days. Next, we will practice together ...

The first method uses a foreach loop $arr = [ [ 'name' => 'testname1', 'age' => 18, ], [ 'name' => 'testname2', 'age' => 19, ], [ 'name' => 'testname3', 'age' => 18, ], ]; $servername = "l ...

Preface: A new sys schema is introduced in MySQL 5.7. Sys is a system library of MySQL. When MySQL 5.7 is installed and initialized with mysqld, sys library will be created automatically. The tables, views, functions and stored procedures in sys libraries can make it easier and faster for us to understand some information of MySQL, such as whic ...

Production and Construction Environment:Operating System: CentOS 7.5Memory size: 32GBHard disk: 1TNote: The optimization of the kernel parameters in the text is modified according to the actual environment.1. Software preparation for installation1.1 Software preparation jdk-8u161-linux-x64 http://www.oracle.com ORACLE linux.x64_11gR2_databas ...

The Web SQL database API is not part of the HTML5 specification, but it is an independent specification that introduces a set of APIs that operate client database using SQL. If you are a Web back-end programmer, it should be easy to understand the operation of SQL. You can also refer to our SQL tutorial Learn more about database operations. ...

Record a little of your last summer vacation study JDBC How to connect? JDBC JDBC, accessing database through java. A java API that executes sql statements. With JDBC, you can easily connect to the database. How to connect? JDBC connecting database can be divided into three steps: creating conn ...

Usually when we refer to database table structure, we are concerned about several attributes:Field name, type, length, whether primary key, whether self-increasing, whether empty, default value, notes.So, what are the properties of using SQL statements to get these attributes under the mainstream databases? MySQL database As the most popular da ...