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sql-server-2008t-sqlappendprefix

Append number to front of string with leading 0

How do I correctly replace the first character with 'M'? Suppose you have a PATIENT_ID_NONNUM = 'M001', and we want 1001 as a result.

UPDATE [HIMC_I2B2_LZ-PROD].[dbo].[I2B2_SRC_BIOMETRICS]
SET PATIENT_ID = CONVERT(NUMERIC(22,0),'1' + CONVERT(NVARCHAR(50),PATIENT_ID))
WHERE SUBSTRING(PATIENT_ID_NONNUM, 1, 1) = 'M'

EDIT:

UPDATE [HIMC_I2B2_LZ-PROD].[dbo].[I2B2_SRC_MEDICATION]
SET PATIENT_ID = CONVERT(NUMERIC(22,0),CONVERT(NVARCHAR(50),'1') + CONVERT(NVARCHAR(50),SUBSTRING(PATIENT_ID_NONNUM, 2, LEN(PATIENT_ID_NONNUM))))
WHERE SUBSTRING(PATIENT_ID_NONNUM, 1, 1) = 'M'
Solution

  • I find STUFF() (an often overlooked function) and LEFT() are a little more readable, but others may disagree:

    UPDATE [HIMC_I2B2_LZ-PROD].[dbo].[I2B2_SRC_BIOMETRICS]
SET PATIENT_ID = CAST(STUFF(PATIENT_ID_NONNUM, 1, 1, '1') AS NUMERIC(22,0))
WHERE LEFT(PATIENT_ID_NONNUM, 1) = 'M'