https://www.postgresqltutorial.com › postgresql-tutorial › postgresql-coalesce
PostgreSQL COALESCE() Function - PostgreSQL TutorialLet’s take some examples of using the COALESCE() function. 1) Basic PostgreSQL COALESCE () function examples. The following example uses the COALESCE() function to return the first non-null argument: SELECT COALESCE (1, 2); Code language: SQL (Structured Query Language) (sql)
SQL Server supports ISNULL function that replaces NULL with a specified replacement value:. ISNULL(expression, replacement) If the expression is NULL, then the ISNULL function returns the replacement.Otherwise, it returns the result of the expression.. PostgreSQL does not have the ISNULL function. However, you can use the COALESCE function which provides similar functionality.
https://stackoverflow.com › questions › 27479180
Using COALESCE to handle NULL values in PostgreSQLYou can use COALESCE in conjunction with NULLIF for a short, efficient solution: COALESCE( NULLIF(yourField,'') , '0' ) The NULLIF function will return null if yourField is equal to the second value ('' in the example), making the COALESCE function fully working on all cases:
https://www.enterprisedb.com › postgres-tutorials › how-use-coalesce-postgresql
How to use COALESCE in PostgreSQL - EDBThe COALESCE function returns the first non-NULL expression in the specified list. If all the arguments are NULL then it will return NULL as its output. The supported syntax is: COALESCE(value_1,value_2,value_3,........value_n) The parameters or arguments are: value_1,value_2,value_3,........value_n.
https://www.postgresql.org › docs › current › functions-conditional.html
PostgreSQL: Documentation: 17: 9.18. Conditional ExpressionsCOALESCE(value [, ...]) The COALESCE function returns the first of its arguments that is not null. Null is returned only if all arguments are null. It is often used to substitute a default value for null values when data is retrieved for display, for example: SELECT COALESCE(description, short_description, '(none)') ...
https://docs.postgresql.fr › 10 › functions-conditional.html
9.17. Expressions conditionnelles - PostgreSQLLa fonction COALESCE renvoie le premier de ses arguments qui n'est pas nul. Une valeur NULL n'est renvoyée que si tous les arguments sont nuls. Cette fonction est souvent utile pour substituer une valeur par défaut aux valeurs NULL lorsque la donnée est récupérée pour affichage. Par exemple :
https://www.sqlshack.com › learn-the-postgresql-coalesce-command
Learn the PostgreSQL COALESCE command - SQL ShackCoalesce in PostgreSQL. The coalesce function’s role is to return the first non-null value it encounters when reading from left to right. In addition, it can replace null values with a specified non-null value. The Coalesce function requires a minimum of two inputs.
https://docs.postgresql.fr › 13 › functions-conditional.html
9.18. Expressions conditionnelles - PostgreSQLCOALESCE(value [, ...]) La fonction COALESCE renvoie le premier de ses arguments non NULL. NULL est renvoyé seulement si tous les arguments sont NULL. Elle est souvent utilisée pour substituer une valeur par défaut pour les valeurs NULL quand les données sont récupérées pour affichage. Par exemple :
https://www.tutorialsteacher.com › postgresql › coalesce-function
PostgreSQL COALESCE Function: Get First Non-NULL ValueIn PostgreSQL, the COALESCE () function is used to get the first non-null value among the specified arguments. It returns the first of its arguments that is not null. If all arguments are NULL, it will return a NULL value. It is often used to substitute a default value for null values.
https://www.stratascratch.com › blog › sql-coalesce-function-a-guide-for-postgresql-users
SQL COALESCE() Function: A Guide for PostgreSQL UsersLearn how to handle null values with ease and efficiency using the versatile COALESCE() function in PostgreSQL, with practical examples and insights.
https://www.mazer.dev › en › databases › postgresql › posts › postgresql-guide-coalesce-function
PostgreSQL COALESCE Function: A Comprehensive GuideThis example demonstrates how to handle null or empty string values in categorical data in PostgreSQL using COALESCE and CASE WHEN. It showcases the utility of these functions in data cleaning and management, particularly in complex grouping and summing operations.
