REPLACE function is used to replace text string or its parts. It belongs to the category of string functions. I created big overview of T-SQL text functions some time ago.

SQL REPLACE Syntax (3 arguments)

SELECT REPLACE(<Column with text in which we replace part of the text>, <The string we want to replace>, <New string>)
FROM dbo.Table

Function has 3 arguments:

1. Text field in which the full or partial text replacement is performed
2. Replaced string
3. New string

Example of REPLACE usage

Create a variable of type text, where there will be dashes instead of spaces. Use REPLACE to replace the “-” character with a space ” ”

DECLARE @String AS VARCHAR(255) = 'Hi,-I'm-the-text';
SELECT REPLACE(@String,'-',' ') AS String_after_Replace;