How a table structure is modified in SQL?

Question

The SQL ALTER TABLE command is used to change the structure of an existing table. It helps to add or delete columns, create or destroy indexes, change the type of existing columns, or rename columns or the table itself. It can also be used to change the comment for the table and type of the table. 7 апр. 2022 г.

How do you modify the structure of a table?

Use MODIFY STRUCTURE to change the structure of the current table by adding or deleting fields, or changing a field name, width, or data type. Issuing the MODIFY STRUCTURE command opens the Table designer, an interactive environment in which you can create or modify the structure of a table.

What is the modification of table?

Elements in a table can be inserted, changed, and deleted. These functions are all performed by the WRITE/TABLE or COPY commands (See Table 5.4). The element to be modified must be defined by giving its column and row location. An element is deleted if the value is set to NULL.

In which view the table structure can be modified?

The properties of a table can be modified in the table view properties.

How can I tell if a SQL table is modified?

The query: SELECT name AS TableName, create_date AS CreatedDate, modify_date as ModifyDate FROM sys. tables order by ModifyDate; ...will tell me the last time a table was created and modified (from a DDL perspective).

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