![]() This function returns the total number of records in the COMPANY table. Illustrate the result of the step by using the following snapshot. The following example illustrates creating and calling a standalone function. Now we will modify the SQL query in a text editor and then we will close the text editor. For backward compatibility, the name can be enclosed by single quotes. Here, we use this option for PostgreSQL, it Can be SQL, C, internal, or the name of a user-defined procedural language. Plpgsql is the name of the language that the function is implemented in. The AS keyword is used for creating a standalone function. The return_datatype can be a base, composite, or domain type, or can reference the type of a table column.įunction-body contains the executable part. RETURN clause specifies that data type you are going to return from the function. The function must contain a return statement. option allows modifying an existing function. Next, specify the datatype of the returned value after the returns keyword. A function can have zero or many parameters. Then, specify the function parameter list surrounded by parentheses after the function name. RETURNS return_datatype AS $variable_name$įunction-name specifies the name of the function. If you want to replace the existing function, you can use the or replace keywords. The basic syntax to create a function is as follows −ĬREATE FUNCTION function_name (arguments) ![]() , '-', 'g'), then all of the dollars would be replaced - and you can do that anyway with the (much cheaper) REPLACE() function. Functions allow database reuse as other applications can interact directly with your stored procedures instead of a middle-tier or duplicating code.įunctions can be created in a language of your choice like SQL, PL/pgSQL, C, Python, etc. Note that this will only replace the first instance of because the 'g' (global) flag isn't present - if the code read. PostgreSQL functions, also known as Stored Procedures, allow you to carry out operations that would normally take several queries and round trips in a single function within the database.
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