The primary key is a column in a table. The primary key needs a unique value, which needs to come from somewhere. The sequence is a feature by some database products which just creates unique values. It just increments a value and returns it. The special thing about it is: there is no transaction isolation, … Read more
It would not be a good idea to rollback sequences. Imagine two transactions happening at the same time, each of which uses the sequence for a unique id. If the second transaction commits and the first transaction rolls back, then the second inserted a row with “2” while the first rolls the sequence back to … Read more
The parentheses are misplaced: SELECT setval(‘payments_id_seq’, 21, true); — next value will be 22 Otherwise you’re calling setval with a single argument, while it requires two or three. This is the same as SELECT setval(‘payments_id_seq’, 21)
— Login to psql and run the following — What is the result? SELECT MAX(id) FROM your_table; — Then run… — This should be higher than the last result. SELECT nextval(‘your_table_id_seq’); — If it’s not higher… run this set the sequence last to your highest id. — (wise to run a quick pg_dump first…) BEGIN; … Read more