Temporary Tables in SQL

Syntax

CREATE TEMPORARY TABLE temp_table_name (
    column1 datatype,
    column2 datatype,
    ...
);

Example

CREATE TEMPORARY TABLE #temp_table (
    id INT,
    name VARCHAR(50),
    age INT
);

Output

No output is generated when creating a temporary table.

Explanation

A temporary table is a table that is only visible and accessible within the session where it was created. These tables are automatically dropped when the session ends or when the connection is closed. Temporary tables are often used when we need to store some data temporarily that will be used in a specific query or set of queries.

Use

Temporary tables are used in situations where we need to store data temporarily and want to avoid creating permanent tables in the database. Some common use cases are:

• Storing intermediate results of complex queries
• Creating a subset of data from a larger table for faster processing
• Storing data to be used in multiple queries throughout a session

Important Points

• Temporary tables are only visible and accessible within the session that created them.
• Temporary tables are automatically dropped when the session ends or the connection is closed.
• Temporary tables can be created using the same syntax as regular tables.
• Data can be inserted, updated, or deleted from temporary tables just like regular tables.
• Temporary tables can be used in joins, subqueries, and other SQL operations just like regular tables.
• Temporary tables can be useful for improving query performance and managing complex data transformations.

Summary

Temporary tables are a powerful tool in the SQL developer's toolkit. They allow us to store data temporarily and avoid cluttering our database with unnecessary permanent tables. By creating temporary tables, we can improve query performance, manage complex transformations, and streamline our database architecture. To use temporary tables, simply create them using the same syntax as regular tables and enjoy their many benefits.