You almost had it, but better start here plpgsql Some will point that PL/pgSQL is not the only way to write Stored Procedures for PostgreSQL and they will be right (that’s one of the advantages of Postgres), but on the other hand PL/pgSQL is nice and relatively easy to start with.
Basically correct. The important difference is that SET is an SQL command while the other two are psql meta-commands – indicated by the leading \. SET is an SQL command to change run-time parameters. It is executed on the server and has nothing to do with psql per se. \set is a psql meta-command: Sets … Read more
It is not possible, and may not ever be possible, to assign a foreign key to a json property. It’d be a major and quite complicated change to PostgreSQL’s foreign key enforcement. I don’t think it’s impossible to do, but would face similar issues to those experienced by the foreign-keys-to-arrays patch. With 9.4 it’ll be … Read more
Here I provide a workaround for the question, and not the title of this post. A better answer to the post overall would probably address configuring SSL for the local machine. I arrived here trying to resolve the problem of finishing that Heroku tutorial mentioned in the question and setting up the Postgres database to … Read more
Pass the returned user_id set as array. Create the function to accept an integer array create function get_timeinstate ( user_id_set integer[], another_param… Then call it passing the array generated by array_agg get_timeinstate( ( select array_agg(userid) from “UserState” where ctime>’2014-07-14′::timestamp ), another_param ); Inside the function: where “UserState”.userid = any (user_id_set) BTW if you are using … Read more
There are a few things wrong with your code. You never told your app to run. When you’re ready creating your routes you should start your server with: app.listen(<port on which the server should run here>); Also you have an Express app and a router in the same file. The router should only be used … Read more
Citus Data has developed an open source columnar store extension for PostgreSQL. It is available under the Apache License v2.0. It supports PostgreSQL 9.3 and higher. First, creation the extension and a foreign server: CREATE EXTENSION cstore_fdw; CREATE SERVER cstore_server FOREIGN DATA WRAPPER cstore_fdw; Next, create some foreign tables: CREATE FOREIGN TABLE customer_reviews ( customer_id … Read more
Redis will be faster than Postgres because Pg offers reliability guarantees on your data (when the transaction is committed, it is guaranteed to be on disk), whereas Redis has a concept of writing to disk when it feels like it, so shouldn’t be used for critical data. Redis seems like a good option for your … Read more
In SQL the AND operator takes “precedence” over OR operator. PostgreSQL adheres to the spec here. You can the exact precedence in PostgreSQL in the docs Lexical Structure: Operator Precedence. So in your case, the result will be the same. However, it’s much easier, and cleaner to simply use the parentheses.
There is an equivalent. It’s called a CASE statement. There are two forms of CASE: Simple CASE: CASE search-expression WHEN expression [, expression [ … ]] THEN statements [ WHEN expression [, expression [ … ]] THEN statements … ] [ ELSE statements ] END CASE; Searched CASE: CASE WHEN boolean-expression THEN statements [ WHEN … Read more