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This article mainly explains the "Oracle list field addition, deletion, modification and renaming operation", the article explains the content is simple and clear, easy to learn and understand, the following please follow the editor's ideas slowly in depth, together to study and learn "Oracle list field addition, deletion, modification and renaming operation" bar!

Add field syntax: alter table tablename add (column datatype [default value] [null/not null], … .)

Description: alter table table name add (whether the default value of field name field type is empty)

Example: alter table sf_users add (HeadPIC blob)

Example: alter table sf_users add (userName varchar2 (30) default 'empty' not null)

Modify the syntax of the field: alter table tablename modify (column datatype [default value] [null/not null], … .)

Description: alter table table name modify (whether the default value of field name field type is empty)

Example: alter table sf_InvoiceApply modify (BILLCODE number (4))

Syntax for deleting fields: alter table tablename drop (column)

Description: alter table table name drop column field name

Example: alter table sf_users drop column HeadPIC

Rename the field:

Description: alter table table name rename column column name to new column name (where: column is the keyword)

Example: alter table sf_InvoiceApply rename column PIC to NEWPIC

Rename the table:

Description: alter table table name rename to new table name

Example: alter table sf_InvoiceApply rename to sf_New_InvoiceApply

Thank you for your reading, the above is the "Oracle table column field increase, delete, modify and rename operation" content, after the study of this article, I believe you on the Oracle table column field increase, delete, modify and rename operation of this problem has a deeper understanding, the specific use of the need for you to practice and verify. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!

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