First, basic usage
1. Add Column
ALTER TABLE Tbl_name add col_name type
For example, add a column of weight to the pet table,
Mysql>alter table Pet Add weight int;
2. Delete Column
ALTER TABLE Tbl_name drop col_
MySQL database ALTER command explanation, MySQL ALTER command explanation
MySQL is a Relational Database Management System. This so-called "Relational" can be understood as "tables". A Relational Database consists of one or more tables.
When we need
The following articles mainly describe the actual operations of modifying the alter TABLE structure in MySQL. If you are interested in the actual operations of modifying the alter TABLE structure in MySQL, you can browse the following articles, the
ALTER TABLE allows you to modify the structure of an existing table. For example, you can add or delete columns, create or eliminate indexes, change the type of existing columns, or rename columns or the table itself. You can also change the
We know that,MySQLDatabases are often combined with PHP to develop powerful applications. So for those who are new to PHP programming, it is necessary to understand some simple MySQL database operations. In this article, we useAlter tableStatement
Mysql Statement Change table structure ALTER (ALTER)Original
Table A For example:
The code is as follows
Copy Code
CREATE TABLE A (A_a int NOT NULL,A_b int NOT NULL,A_c Char) Engine=innodb Charset=utf8;
Syntax:
MySQL is a relational database (RelationalDatabaseManagementSystem ). This article focuses on the alert commands of the mysql Database. This article is very detailed and has reference value. if you are interested, join us and learn that MySQL is a
MySQL study Note 5: modifying the table (altertable) bitsCN.com we will inevitably consider the week before creating the table. Therefore, the alter table statement is required to modify the table later.
Modify table name
Mysql> alter table
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