Location of #th iteration of a character or a word in a sql text field
There's no specific support for this in Transact-SQL.

You could write your own function using CHARINDEX.

Alternatively, you could use a library that someone else has already written, for example the SQLsharp SQLCLR extension library. Among the over 240 functions and procedures is SQL#.String_NthIndexOf:

-- Result: 13
SELECT SQL#.String_NthIndexOf
(
    N'abc abc abc abc abc',  -- Input string
    N'abc',                  -- Search for this
    1,                       -- Starting at position
    4,                       -- Nth occurrence
    1,                       -- Case sensitive
    0                        -- Don't count overlaps
);


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