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Editor to share with you how to modify the table structure in the sql sentence, I believe that most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

The command in the SQL statement to modify the table structure is ALTER TABLE.

ALTER TABLE statement

The ALTER TABLE statement is used to add, delete, or modify columns in an existing table.

SQL ALTER TABLE syntax

To add columns to the table, use the following syntax:

ALTER TABLE table_nameADD column_name datatype

To delete columns from a table, use the following syntax (note that some database systems do not allow this way to delete columns from a database table):

ALTER TABLE table_nameDROP COLUMN column_name

To change the data type of the columns in the table, use the following syntax:

SQL Server / MS Access:

ALTER TABLE table_nameALTER COLUMN column_name datatype

My SQL / Oracle:

ALTER TABLE table_nameMODIFY COLUMN column_name datatype

Oracle version after 10G:

ALTER TABLE table_nameMODIFY column_name datatype; above is all the contents of the article "how to modify the table structure in the sql sentence". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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