When you drop database all tables and data containing within it are lost. Dropping a Databaseĭrop a database by selecting Delete on the node shortcut menu. You can not rename database in other MySQL versions. In Database Explorer, right-click a database node and select Edit Database on the shortcut menu.ĭatabase can be renamed only on MySQL 5.1.7 - 5.1.23 and 6.0.0.Click OK, and, if specified name is unique, the database will appear in Database Explorer.
Select New Database on the Database menu. In Database Explorer, right-click a connection node and select New Database. In the later versions of MySQL, Charset and Collation are added. In MySQL 3.23 database has only one property - Name. This is a very simple example, but hopefully you can see how this will help when your database schema has 10, 20, or more tables with MySQL foreign key relationships.Database is MySQL schema object that represents a folder containing tables. That's all you have to do for this MySQL DROP TABLE foreign key technique just set the MySQL FOREIGN_KEY_CHECKS variable before and after all your drop statements, and you're DROP TABLE statements will work just fine, regardless of foreign keys. MySQL DROP TABLE foreign keys - The better wayīut fortunately, with the MySQL FOREIGN_KEY_CHECKS variable, you don't have to worry about the order of your DROP TABLE statements at all, and you can write them in any order you like - even the exact opposite - like this: That was the only order in which the MySQL tables could be dropped. With all tables highlighted, right-click on one of the tables and. Click on the first table on the list, then hold SHIFT and click on the last table. Click on your database name, then click the Tables menu. The way I used to do this was drop these tables in this exact order: Finally, if you’re using MySQL Workbench to manage your database, you follow these steps to drop all tables: Navigate to the Schemas tab. First, imagine that you have database tables named customers, orders, order_details, and orders has a foreign key back to customers, and order_details has a foreign key back to orders. Here's a simple example of how this works.
Inspired by Fabians answer, but lighter and catches empty databases.This approach generates the script via MYSQL query, then feeds it back to MYSQL. MySQL DROP TABLE foreign keys simple example - The old way Both of these approaches remove all databases, besides mysql, informationschema and performanceschema. After that, you run your MySQL CREATE TABLE statements, then turn the foreign_key_check back on.
MySQL essentially turns off the foreign key checks, letting you drop your tables in any order desired. In short, MySQL has a variable named FOREIGN_KEY_CHECKS that you can set just before and just after all your MySQL DROP TABLE statements, and with this variable set, the order of your drop statements doesn't matter. Until I knew how to properly approach this problem I used to write my DDL (the MySQL drop table statements) in a very specific order - which was very time-consuming - but fortunately there's a much easier solution to this problem with MySQL. When you do this, you'll often run into problems dropping the old database tables because of the foreign key relationships between the tables.įor instance, if an orders table has a foreign key link back to a customers table, you can't drop the customers table until you first drop the orders table - and any other database table that has a foreign key relationship back to the customers table. With MySQL - and any other database - any time you want to rebuild your database schema, the first thing you normally do is drop all your old database tables with MySQL drop table statements, and then rebuild them with MySQL create table statements. Is there something I can do to work around this DROP TABLE foreign keys problem? Solution MySQL “DROP TABLE” FAQ: Help, my MySQL database tables have a lot of foreign keys, and as a result it's a pain to use the MySQL DROP TABLE command in my scripts they keep failing because of all the foreign keys.
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