How to find all tables that have foreign keys that reference particular table.column and have values for those foreign keys?

Here you go:

USE information_schema;SELECT *FROM  KEY_COLUMN_USAGEWHERE  REFERENCED_TABLE_NAME = 'X'  AND REFERENCED_COLUMN_NAME = 'X_id';

If you have multiple databases with similar tables/column names you may also wish to limit your query to a particular database:

SELECT *FROM  KEY_COLUMN_USAGEWHERE  REFERENCED_TABLE_NAME = 'X'  AND REFERENCED_COLUMN_NAME = 'X_id'  AND TABLE_SCHEMA = 'your_database_name';

MySQL 5.5 Reference Manual: "InnoDB and FOREIGN KEY Constraints"

SELECT  ke.REFERENCED_TABLE_SCHEMA parentSchema,  ke.referenced_table_name parentTable,  ke.REFERENCED_COLUMN_NAME parentColumnName,  ke.TABLE_SCHEMA ChildSchema,  ke.table_name childTable,  ke.COLUMN_NAME ChildColumnNameFROM  information_schema.KEY_COLUMN_USAGE keWHERE  ke.referenced_table_name IS NOT NULL  AND ke.REFERENCED_COLUMN_NAME = 'ci_id' ## Find Foreign Keys linked to this Primary KeyORDER BY  ke.referenced_table_name;

This solution will not only display all relations but also the constraint name, which is required in some cases (e.g. drop constraint):

SELECT    CONCAT(table_name, '.', column_name) AS 'foreign key',    CONCAT(referenced_table_name, '.', referenced_column_name) AS 'references',    constraint_name AS 'constraint name'FROM    information_schema.key_column_usageWHERE    referenced_table_name IS NOT NULL;

If you want to check tables in a specific database, add the following:

AND table_schema = 'database_name';