Use the following syntax of the LAG() function in PostgreSQL as mentioned and explained below: LAG(expression [,offset [,default_value]]) OVER ( [ORDER BY sort_expression [ASC | DESC]] ) The above code suggests: - TheLAGkeyword is used to specify the name of the function and then its...
This post illustrates the basic syntax and working of the JSON_ARRAY_ELEMENTS() function in Postgres using practical examples. How to Use JSON_ARRAY_ELEMENTS() Function in PostgreSQL? The JSON_ARRAY_ELEMENTS() is a built-in JSON function that accepts a JSON array as an argument and expands ...
Combine with Other Functions:Use in conjunction with other PostgreSQL functions for advanced data operations. Syntax: unnest(anyarray) Return Type: setof anyelement PostgreSQL Version: Available since PostgreSQL 9.3 Example: PostgreSQL UNNEST() function Basic Usage Code: -- Selecting and unnesting an ...
Functions in PostgreSQL can be created in many languages such as SQL, PL/pgSQL, Python, C, and more. Syntax: CREATE [OR REPLACE] FUNCTION function_name (arguments) RETURNS return_datatype AS $variable_name$ DECLARE declaration; [...] BEGIN < function_body > [...] RETURN { variable_na...
Summary: in this tutorial, you will learn how to use the PostgreSQL NULLIF() function to handle null values. Introduction to PostgreSQL NULLIF function The NULLIF() function is one of the most common conditional expressions provided by PostgreSQL. Here’s the basic syntax of the NULLIF function...
In the above syntax: -“str” represents a string to be converted into an array. -“sep” represents a splitter based on which the given string will be split to array elements. -“text” is an optional parameter that replaces the NULL values with the specified text. ...
COALESCEandNULLIFare two PostgreSQL functions to handleNULLvalues. The key difference between them lies in their purpose. The first is used to return the first non-NULLvalue from a list of arguments. On the other hand,NULLIFcompares two expressions: NULLIF(expression1, expression2). It returnsNU...
PostgreSQL SyntaxPostgreSQL Operators PostgreSQL SELECT PostgreSQL SELECT DISTINCT PostgreSQL WHERE PostgreSQL ORDER BY PostgreSQL LIMIT PostgreSQL MIN and MAX PostgreSQL COUNT PostgreSQL SUM PostgreSQL AVG PostgreSQL LIKE PostgreSQL IN PostgreSQL BETWEEN PostgreSQL AS PostgreSQL Joins PostgreSQL INNER JOIN ...
Syntax: concat(<string1>,[<string2>,<string3>,...]) string1, string2, string3, ...: The strings to be concatenated. These can be column names, literals, or expressions. PostgreSQL Version: 9.3 Visual Presentation of PostgreSQL CONCAT() function ...
Basic Syntax The below snippet illustrates the usage of the NULLIF() function in PostgreSQL: NULLIF(argument_1, argument_2); How to Use NULLIF Function in PostgreSQL? The NULLIF() function can be better understood by implementing it practically. So, let’s do it!