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11 wrz 2012 · The following query gives the list of all the primary keys in the given database. SELECT DISTINCT TABLE_NAME ,column_name FROM INFORMATION_SCHEMA.key_column_usage WHERE TABLE_SCHEMA IN ('*your_db_name*');
14 paź 2008 · select table_name,column_name,constraint_name, referenced_table_name,referenced_column_name from information_schema.key_column_usage where referenced_table_schema = (select database()) and referenced_table_name = '<table>' \g for a column:
21 mar 2024 · Below are five ways to get the primary key column/s from an existing table in MySQL. The SHOW KEYS Statement. In MySQL we can use the SHOW KEYS statement to get the primary key for a given table: SHOW KEYS FROM Person . WHERE Key_name = 'PRIMARY'; Example result:
The FOREIGN KEY constraint is used to prevent actions that would destroy links between tables. A FOREIGN KEY is a field (or collection of fields) in one table, that refers to the PRIMARY KEY in another table.
To find out what tables the default database contains (for example, when you are not sure about the name of a table), use this statement: mysql> SHOW TABLES; +---------------------+. | Tables_in_menagerie |. +---------------------+. | event |.
The PRIMARY KEY constraint uniquely identifies each record in a table. Primary keys must contain UNIQUE values, and cannot contain NULL values. A table can have only ONE primary key; and in the table, this primary key can consist of single or multiple columns (fields).
In this tutorial, you will learn how to use MySQL primary key constraint to create the primary key for a table.
