Joining two table

Question

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In this Table1 and Table2 (AttendanceDate,EmployeeCode) are PRIMARY Key.. How can we replace table1 value with table2 where ever AttendanceDate and EmployeeCode will match..

Like Result table..

Use an `outer join` with `coalesce`... Try something and let us know where you're having troubles. — sgeddes, Mar 10 '15 at 13:10
I think your looking for an update statement. Example found in a prior answer: http://stackoverflow.com/questions/224732/sql-update-from-one-table-to-another-based-on-a-id-match — xQbert, Mar 10 '15 at 13:25

score 2 · Accepted Answer · answered Mar 10 '15 at 13:12

try this untested query:

select t1.AttendanceDate, t1.EmployeeCode, case when t2.duration is null then t1.duration else t2.duration end 
from table1 t1 left outer join table t2 on t1.AttendanceDate= t2.AttendanceDate and  t1.EmployeeCode =  t2.EmployeeCode

LeeG · Answer 2 · 2015-03-10T13:24:14.903

-1

This should work.

SELECT Table1.AtendanceDate, Table1.EmployeeCode,
    CASE WHEN Table2.Duration IS NOT NULL THEN Table2.Duration ELSE Table1.Duration END AS Duration
FROM Table1 
LEFT OUTER JOIN Table2 ON Table1.AtendanceDate = Table2.AtendanceDate 
    AND Table1.EmployeeCOde = Table2.EmployeeCode

edited Mar 10 '15 at 13:24

answered Mar 10 '15 at 13:14

LeeG

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Syntax error. And you can't mix datatypes in a COALESCE like that. – jarlh Mar 10 '15 at 13:23
1

That's what I get for not proofreading. I started with a COALESCE and then changed changed my mind. – LeeG Mar 10 '15 at 13:24

Joining two table

2 Answers2