Question

I have two tables namely tenant and unit.

dtleaseto is the column present in tenant table. dtmovein is the
column present in unit table.

I need to update only month and day of a date present in dtleaseto
with the month and day of a period which is one day prior to dtmovein.

E.g. Suppose my dtlease to is 12/20/2012 and dtmovein is 01/01/2011
then my updated dtleaseto will be 12 / 31 /2012.

*Relationship between tenant and unit is tenant.hunit = unit.hmy

Thanks in advance for your help!!! 🙂

Answer 1

Seems like you might want something like this:

UPDATE t
  SET dtleaseto = CONVERT(date, CAST(YEAR(t.dtleaseto) AS CHAR(4)) -- Year of dtleaseto
  +SUBSTRING(CONVERT(CHAR(8),DATEADD(day,-1,u.dtmovein),112),5,4)) -- MMDD part of dtmovein-1 day
FROM tenant t
JOIN unit u on t.hunit = u.hmy