What is the difference between single quotes and double quotes in PostgreSQL?

Question

I am new to PostgresSQL.I tried

select * from employee where employee_name=\"elina\";

But that results error as follows:

E         


        

Answer 1

Well single quotes are used for string literals and double quotes are used for escaping DB objects like table name / column name etc.

Specifically, double quotes are used for escaping a column/table name if it's resemble to any reserve/key word. Though every RDBMS have their own way of escaping the same (like backtique in MySQL or square bracket in SQL Server) but using double quotes is ANSI standard.