I found this piece of code here
WITH ShowMessage(STATEMENT, LENGTH)
AS
(
SELECT STATEMENT = CAST('I Like ' AS VARCHAR(300)), LEN('I Like ')
UNION ALL
SELECT
CAST(STATEMENT + 'CodeProject! ' AS VARCHAR(300))
, LEN(STATEMENT) FROM ShowMessage
WHERE LENGTH < 300
)
SELECT STATEMENT FROM ShowMessage
Output:
I can't get the meaning of the code correctly, especially the usage of length.
Have a look at the query results when you change it to include the LENGTH column.
WITH ShowMessage(STATEMENT, LENGTH)
AS
(
SELECT STATEMENT = CAST('I Like ' AS VARCHAR(300)),
LEN('I Like ')
UNION ALL
SELECT CAST(STATEMENT + 'CodeProject! ' AS VARCHAR(300)),
LEN(STATEMENT) FROM ShowMessage
WHERE LENGTH < 300
)
SELECT STATEMENT,
LENGTH
FROM ShowMessage
You will notice on each recursion the length of the string gets longer.
The recursice loops will end once the leng grows to longer than 300
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