postgresql insert if not exists return id

POSTGRESQL INSERT IF NOT EXISTS RETURN ID HOW TO
POSTGRESQL INSERT IF NOT EXISTS RETURN ID UPDATE

The reason it doesn't show up in the SELECT immediately after the CTEs has to do with the scope of the transaction - the first SELECT shows the service table as it was at the beginning of the transaction - the second shows the state of the table after the transaction.Guide: Insert if not exists, else return id in PostgreSQL So, we can see that service Test1's active field has been set to false and that service Test4 has been added. In the next section, you rerun SELECT * FROM service So, you might think 'Drat, it hasn't worked!' - but in fact, it has worked! Now, the result of the SELECT * FROM service at the end of this query is: name id active Sets the service status = false where a service in the service table isn't present in the api table.

POSTGRESQL INSERT IF NOT EXISTS RETURN ID UPDATE

Inserts new services from the api table into the service table and the second: UPDATE service s SET active = false The first CTE INSERT INTO service (name, id, active) WHERE s.name NOT IN (SELECT name FROM api) RETURNING s.name WHERE a.name NOT IN (SELECT name FROM service) RETURNING name So now, because of PostgreSQL's ability to perform INSERTs and UPDATEs within CTEs, we can now do the following: WITH cte1 (nom) AS

Notice that service Test1 is missing and that service Test4 is an additional service. I've assumed that your API doesn't know the status of the service, so it only has two fields - the name and the name and the id. Now, you receive your data from your API - I'll assume that you put that into some sort of temporary table - the keyword TEMPORARY just means that the table will be dropped at the end of your session - I've tested with both TEMPORARY and normal tables with the fiddle and the results are the same, so we'll go with TEMPORARY: CREATE TEMPORARY TABLE api Populate it with your data: INSERT INTO service VALUES

It's based on Common Table Expressions ( CTEs) and that fact that with PostgreSQL, you can perform not only SELECTs, but also INSERTs, UPDATEs and DELETEs (see here also).įirst, your service table: CREATE TABLE service I think you will want something like the following - see the fiddle here. So if the new list does not have Test3 the existing Test3 row would be updated to show Active as false.

If the newly fetched list from an API does not have one of the existing 'Name's, that is Test1,Test2 or Test3 update that existing row to set the Active column to false.

If a new 'Name' comes up not found in the DB add it as a new row.

If an existing 'Name' is found skip the insert and move on to the next item in the array.

I wanted to have a query or trigger of some sort to run when trying to insert duplicate data to table Services where constrained by the following: I had in mind to just drop all records and add the new ones fetched from the API however considering I have used the Ids for the existing services in other tables and I would still need to reference them I threw that idea out the window and now I am in a bit of a bind.

Likewise is a new service comes onboard it should be added to the current list of available services. The list of services comes from an API and is usually the same set of services, however every now and again the list may be updated and services become inactive and no longer show up in the results from the API call so these services should be updated in our database to reflect active as FALSE.

POSTGRESQL INSERT IF NOT EXISTS RETURN ID HOW TO

I was trying to wrap my head around how to go about doing an update to a table if an updated list of the same table type does not have one or more of its original rows.

Postgresql insert if not exists return id