You can create and use temporary tables in a stored procedure, but the temporary table exists only for the duration of the stored procedure that creates it. When the procedure completes, Adaptive Server automatically drops the temporary table. A single procedure can: Show
Since the temporary table must exist to create procedures that reference it, here are the steps to follow:
You cannot, because the #tempstores table no longer exists. You can also create temporary tables without the # prefix, using create table tempdb..tablename... from inside a stored procedure. These tables do not disappear when the procedure completes, so they can be referenced by independent procedures. Follow the above steps to create these tables. To answer a question that arises from the comments, temporary tables in MySQL are owned by and only available to the client connection (session, thread) that created them, so there's not an isolation issue, but there is the potential issue of your connection having left something there with that name before, either with stale data or a similarly-named table with a different structure, either of which would be less than ideal. The
Important: if you do not have an index on the STATUS column of the BATCH_ITEMS table, this will be one of the two major reasons this procedure is slower than it needs to be. That's going to be essential for performance, either with this code or the existing code. It would probably also be best to index the temporary table, to make life as easy as possible for the optimizer. Note that the column declared must be the same as the name or alias of the column in the
Then instead of an update that use a subquery, this should be a join, since those are generally optimized better in any version of MySQL. This is the other likely reason this procedure may be slower than you expect.
Then return the result-set...
Optionally, you can drop the temporary table... it will be dropped automatically when your session disconnects, or the next time you run this procedure, since we're now explicitly dropping it at the start if you run this again in the same session.
Create MySQL temporary table Temporary Table in MySQL is an extremely useful and flexible feature that enables you to achieve complex tasks quickly. In this tutorial, we'll look at the advantages of using temporary tables as well as the limitations of their usage. Note: How to create MySQL Temporary table To create a Temporary Table in MySQL, we add the TEMPORARY keyword in the CREATE TABLE statement. Most of the queries in the tutorials need Northwind MySQL database, you can download the database script on this page. For example, the following statement creates a temporary table for products above average price. create temporary table tempProductsAboveAvgPrice Temporary Table can only be created as type MEMORY, MyISAM, MERGE, or InnoDB. If you don't specify an engine type when creating the Temporary Table, the default storage engine for the server is used. The default storage engine is set in MySQL server configuration file my.cnf. MySQL manual states: Since MySQL 5.5, InnoDB becomes the default storage engine and most users never changed the default settings, and it's also recommended by MySQL that the default setting should not be changed because of the ACID (Atomicity, Consistency, Isolation, Durability) benefits of InnoDB tables, e.g. transaction safe, referential integrity enforcement, and crash recovery. Now the temporary table tempProductsAboveAvgPrice has been created, you can query it the same way as you do for a permanent table. select * from tempProductsAboveAvgPrice Here is the query result. 25 records returned. You also can create the temporary table tempProductsAboveAvgPrice in 2 steps as shown below. Step 1: create temporary table tempProductsAboveAvgPrice Step 2: insert into tempProductsAboveAvgPrice Now issue a SHOW TABLES command for Northwind database, the temporary table tempProductsAboveAvgPrice is not listed in the result. This is because the SHOW TABLES command only lists permanent tables in the database. Here is the query result of SHOW TABLES command. 9 records returned. Drop Temporary table By default, all the temporary tables created are dropped automatically by MySQL when your database connection is terminated, but you still can manually drop a temporary table by issuing DROP TABLE command. drop table tempProductsAboveAvgPrice When to use MySQL Temporary table The Divide and Conquer rules - this is the single most attractive advantage of using MySQL Temporary Table. Temporary Table offers definite advantages when it's used to hold data returned from a very complex query (so very expensive to create) for temporary use. For example, you need to retrieve a bunch of data from multiple tables with join, union, group by, etc., then you need to do some work on the resulting dataset... Therefore, if you ever find you frequently write complex SQL queries, consider using Temporary Tables to simplify your work. This also makes other people's life easier if they need to maintain your queries or customize for some other uses. Advantages of using Temporary Table
Limitations of using Temporary Table As of MySQL version 5.7, MySQL TEMPORARY tables have the following limitations:
Other tutorials in this category Back to Tutorial Index Page Can we create temporary table in stored procedure in MySQL?A temporary table exists within a session only; therefore, a table created by one session is not visible to another session. For example, Session ID 501 has created a temporary table then session ID 502 cannot access it or manipulate it. Two different sessions can have a temporary table with the same name.
Can we create temporary table in stored procedure?Stored procedures can reference temporary tables that are created during the current session. Within a stored procedure, you cannot create a temporary table, drop it, and then create a new temporary table with the same name.
How do I create a temporary table from another table in MySQL?In MySQL, the syntax of creating a temporary table is the same as the syntax of creating a normal table statement except the TEMPORARY keyword. Let us see the following statement which creates the temporary table: mysql> CREATE TEMPORARY TABLE table_name ( column_1, column_2, ..., table_constraints.
Can we use temporary table in MySQL?You can use the TEMPORARY keyword when creating a table. A TEMPORARY table is visible only within the current session, and is dropped automatically when the session is closed.
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