In PostgreSQL, a constraint is a rule or restriction applied to a column or a group of columns in a table to enforce data integrity. Constraints help maintain the consistency, accuracy, and reliability of the data stored in the database. The...
Constraint of relation does not exist The cause of error: There is no constraint created with the specified name. Check the constraint name. Wrong drop ALTER TABLE test.customers DROP CONSTRAINT fk_address_test; Messages ERROR: constraint “fk_address_test” of relation “customers” does not exist...
Control reaches end of function without return ERROR: control reaches end of function without return The cause of this error is the lack of execution of the command return in the function. Wrong function CREATE OR REPLACE FUNCTION update_customers( p_first_name varchar,...
PostgreSQL duplicate key value violates unique constraint Duplicate key value violates unique constraint in PL/pgSQL Duplicate key The cause of error: Duplicate key value violates unique constraint in PL/pgSQL. The solution is to add unique values when you make insert or...
Duplicate key value violates unique constraint Customers table Id First_name Last_name 1 Tom Green 2 Jacob Logan 3 John Pope insert into customers (first_name, last_name) values ('John', 'Pope'); ERROR: duplicate key value violates unique constraint This error occurs when because on...
