Search for a common prefix between two strings - sql-server

Question

I have a Stored Procedure:
ALTER PROCEDURE [dbo].[traxs_Paybook_Data_Validate]
#session_id varchar(30)
#paybook_start_number varchar(30)
#paybook_end_number varchar(30)
AS
UPDATE traxs_temp..__PaybookImport SET
/* BEGIN CHANGE */
prefix = null,
start_number = CAST(#paybook_start_number AS int),
end_number = CAST(#paybook_end_number AS int)
/* END CHANGE */
WHERE
session_id = #session_id
Values were like:
#paybook_start_number = 100
#paybook_end_number = 200
Now paybook numbers can have a prefix, i.e:
#paybook_start_number = ABC100
#paybook_end_number = ABC200
Prefix is not always the same, neither is its length. I need to find the prefix if one, store it into prefix and remove it from paybook numbers before casting them.
Thanks

Answer 1

Try this:
DECLARE #z VARCHAR(32) = 'ukasd10';
SELECT LEFT(#z, PATINDEX('%[0-9]%', #z) - 1) AS Prefix,REPLACE(SUBSTRING(#z, PATINDEX('%[0-9]%', #z), LEN(#z)), ',', '') AS Digits
and likewise use this logic to update the column Prefix....
Thanks

Answer 2

You need a Function to extract Number/Numeric value from your input string and a function to extract Alphabets from the Input string.
Function To Extract Numbers
CREATE FUNCTION dbo.fn_Extract_Numbers
(
#string NVARCHAR(100)
)
RETURNS INT
AS
BEGIN
DECLARE #int_Value INT;
SELECT #int_Value = LEFT(subsrt, PATINDEX('%[^0-9]%', subsrt + 't') - 1)
FROM (
SELECT subsrt = SUBSTRING(#string, pos, LEN(#string))
FROM (
SELECT #string AS string , PATINDEX('%[0-9]%', #string) AS Pos
) d
) t
RETURN #int_Value;
END
Function To Extract Alphabets
CREATE FUNCTION dbo.fn_Extract_Alphabets
(
#string NVARCHAR(100)
)
RETURNS NVARCHAR(100)
AS
BEGIN
DECLARE #Alpha_Value NVARCHAR(100);
SELECT #Alpha_Value = LEFT(subsrt, PATINDEX('%[^a-z]%', subsrt + 't') - 1)
FROM (
SELECT subsrt = SUBSTRING(#string, pos, LEN(#string))
FROM (
SELECT #string AS string , PATINDEX('%[a-z]%', #string) AS Pos
) d
) t
RETURN #Alpha_Value;
END
Now use these functions inside your stored procedure to extract the Alphabet/Prefix bit and the Number bit and store them in the target columns.
Something like....
ALTER PROCEDURE [dbo].[traxs_Paybook_Data_Validate]
#session_id varchar(30)
#paybook_start_number varchar(30)
#paybook_end_number varchar(30)
AS
DECLARE #Start_Num_Prefix VARCHAR(100);
DECLARE #End_Num_Prefix VARCHAR(100);
DECLARE #Start_Num_Numbers INT;
DECLARE #End_Num_Numbers INT;
SELECT #Start_Num_Prefix = dbo.fn_Extract_Alphabets(#paybook_start_number)
SELECT #End_Num_Prefix = dbo.fn_Extract_Alphabets(#paybook_end_number)
SELECT #Start_Num_Numbers = dbo.fn_Extract_Numbers(#paybook_start_number)
SELECT #End_Num_Numbers = dbo.fn_Extract_Numbers(#paybook_end_number)
..... rest of your procedure and so on....