Does REPLACE function in SQL Server accept input from a table for 'string_pattern' parameter?

Question

I\'m still learning my ropes with SQL Server and maybe this question sounds very naive/ridiculous. Please bear with me on this. :)

I saw a function in SQL Server defined

Answer 1

This is a hacky trick called Quirky Update

This is slow and in most cases something one should avoid

Some examples:

DECLARE @tbl TABLE(SomeInt INT);
INSERT INTO @tbl VALUES (1),(2),(3);

DECLARE @SumOfInts INT=0
SELECT @SumOfInts = @SumOfInts + SomeInt FROM @tbl;
SELECT @SumOfInts; --SELECT SUM(SomeInt) FROM @tbl is clearly better...)

String concatenation

DECLARE @tbl2 TABLE(SomeText VARCHAR(100));
INSERT INTO @tbl2 VALUES ('a'),('b'),('c');

DECLARE @ConcatString VARCHAR(100)='';
SELECT @ConcatString = @ConcatString + ', ' + SomeText FROM @tbl2;
SELECT @ConcatString;

Better was the usual approach with FOR XML PATH('') and STUFF(), which is a hacky workaround too. (Newer versions will bring a built-in function at last!)

With REPLACE it works!

This Quirky Update is the only way I know to use a table's values for a step-by-step replacement of many values you can maintain in a table dynamically:

Look at this:

DECLARE @ReplaceValues TABLE(this VARCHAR(100),[by] VARCHAR(100));
INSERT INTO @ReplaceValues VALUES('$',' Dollar'),('€',' Euro'),('abbr.','abbreviations');

DECLARE @SomeText VARCHAR(MAX)=
'This text is about 100 $ or 100 € and shows how to replace abbr.!';

SELECT @SomeText=REPLACE(@SomeText,this,[by]) FROM @ReplaceValues;

SELECT @SomeText;

The result

--This text is about 100  Dollar or 100  Euro and shows how to replace abbreviations!