![]() ![]() ![]() Here’s the syntax of MySQL DROP INDEX command DROP INDEX constraintname ON tablename algorithmoption lockoption In the above query, constraintname is the name of constraint, and tablename is your database table name. * Dynamically allocated and run statement. We will use MySQL DROP INDEX query to remove existing index from a table. SET := CONCAT('ALTER TABLE ',pv_table_name,'DROP INDEX ',pv_index_name) * Set a session variable with two parameter markers. * Declare a local variable for the SQL statement. (Persistent Stored Module) or stored procedure. If I use: mysql> drop database database name I'll destroy the database completely and I won't be able to create tables again. Then I use this command to drop a table: mysql> drop table table name But what I need is the command line to drop all tables in the database. ![]() Alternatively, MySQL also allows to drop indexes using the ALTER TABLE command. 30 Usually I open Terminal.app and connect to a remote MySQL database. Change the default semicolon delimiter to write a PSM To drop a non-primary key index, use the DROP INDEX command: DROP INDEX. Reset the default semicolon delimiter.ĭROP PROCEDURE IF EXISTS dropIndexIfExists WHERE s.index_schema = database ( ) AND s.table_name = pv_table_nameĪND s.index_name = pv_index_name ) THEN /* Dynamically allocated and run statement. This document describes how to manually delete a MySQL database from a cPanel & WHM server. */ IF EXISTS ( SELECT NULL FROM information_schema.statistics s */ SET := CONCAT ( 'ALTER TABLE ' ,pv_table_name, 'DROP INDEX ' ,pv_index_name ) /* Check if the constraint exists. Does anybody know how to resolve it mysql innodb mysql-5. Even we are unable to perform any operation on that particular table. */ DECLARE stmt VARCHAR ( 1024 ) /* Set a session variable with two parameter markers. 16 We are trying to drop one table but it's getting hanged, and when we see the 'SHOW PROCESSLIST' command it's showing as 'waiting for meta data lock'. ( pv_table_name VARCHAR ( 64 ), pv_index_name VARCHAR ( 64 ) ) BEGIN /* Declare a local variable for the SQL statement. DROP PROCEDURE IF EXISTS dropIndexIfExists - Change the default semicolon delimiter to write a PSM - (Persistent Stored Module) or stored procedure. MySQL won't let it delete under either circumstance.- Conditionally drop the procedure. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more. So, MySQL fails on both statements, whereas PostgreSQL's solution is (IMHO and as usual) superior - it "forces" the CASCADE if it's explicitly invoked. W3Schools offers free online tutorials, references and exercises in all the major languages of the web. CASCADE to drop the dependent objects too Method 1: MySQL Drop All Tables with SQL Step 1: Generate a List of Drop Table Statements For All Tables Step 2: Copy and Paste The Results Into a New Window. However, a big caveat to the logic argument - PostgreSQL also doesn't allowīut with a far more informative error message: ERROR: cannot drop table foo because other objects depend on itĭETAIL: constraint asdf on table bar depends on table foo Take a look at the fiddle here and it's fairly clear (and actually logical enough in one sense) if you reflect on it - at least to me it is! The referential constraint exists on the table bar and not on foo - therefore deleting foo has no effect on that constraint - and the system won't let you delete the parent table, but will let you delete the parent record. This function takes two parameters and returns TRUE on success or FALSE on failure. ![]() So, (for the MySQL family) the DRI (Declarative Referential Integrity) works on the level of records and not on a table level. PHP uses mysqli query() or mysqlquery() function to drop a MySQL table. INSERT INTO bar VALUES(3), (3), (45), (7), (7) SQL dropping selected row from table Ask Question Asked 5 years, 1 month ago Modified 5 years, 1 month ago Viewed 653 times 0 I am new to SQL and do not understand how to drop rows from a table. Some values: INSERT INTO foo VALUES (3), (45), (7) I don't think that's how CASCADE works with MySQL derivatives!ĬONSTRAINT asdf FOREIGN KEY (x) REFERENCES foo(x) ON DELETE CASCADE ![]()
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