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This article mainly introduces how to modify the field properties of mysql, the article introduces in great detail, has a certain reference value, interested friends must read it!

In mysql, you can modify field properties using the alter command, which is used to modify the data table name or the data table field, with the syntax "alter table table name modify COLUMN field name new data type".

The operating environment of this tutorial: windows10 system, mysql8.0.22 version, Dell G3 computer.

Mysql > alter table table name modify column field name type.

The city field of the address table in the database is varchar (30), and the modification type can be used (careful modification of the type may cause errors in the original data).

Mysql > alter table address modify column city char (30); modify length can be used (modify length to ensure that it is not short and existing data, to ensure that the original data does not make mistakes) mysql > alter table address modify column city varchar (50)

Alter table table name modify column field name type; the length of the title field in the news table was originally 100 characters, but now it needs to be changed to 130 characters.

Mysql modify the field type: alter table news modify column title text; I found that using this sentence sql can also directly modify the field's original type!

Usually can be written as alter table table name modify column column name new column type for example: student table column sname type is char (20), now to change to varchar (20), the SQL statement is as follows: alter table student modify column sname varchar (20)

A way to modify both the column name and the data type of the column: usually you can write the alter table table name change column the old column name the new column name the new column type the column sname in the student table is char (20), now you want to change it to stuname varchar (20) alter table student change column sname stuname varchar (20)

The above is all the content of the article "how to modify Field Properties by mysql". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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