sql server programming: I have 3 tables. Table1(time,readingA) Table2(time,readingB)
table3(time,readingC)
Now the time can be same and it can be different. Now i want to know
how do i join so that i get the data: time,readingA,readingB,readingC

If the time is same then it is fine, but if the time is not same in
two tables for eg : if table1 has a record for time 12:30 and Table2
and table3 does not have that time then it should show data from
table1 and the readingB and readingC will be blank.


I hope my question is clear.

Hi

If you are not interested in the time then you may not want to truncate
everything to midnight when they are inserted (which if you don't have a time
portion on your date/time will happen anyhow). The isssue then is what will
happen if there are multiple records for each day? If the time is require for
some other reason you can also use the convert function to compare the date
part of the datetime

SELECT CONVERT(char(8),T1.time,112) AS Time, T1.readingA, T2.readingB,
T3.readingC
FROM Table1 T1
JOIN Table2 T2 ON CONVERT(char(8),T1.time,112) = CONVERT(char(8),T2.time,112)
JOIN Table3 T3 ON CONVERT(char(8),T1.time,112) = CONVERT(char(8),T3.time,112)

John

[quoted text, click to view]