Question

I have a table that contains records with a column indicates the Date. Given a record, I would like to select all records that are in the same week as the record. How can SQL do that?

I should say that I’m using SQLite.

Answer 1

You can use DATEPART with wk to get the current week. Then just check for equality.
In this case, I have also checked yy to make sure that you do not check the year of a previous week.

SELECT * 
FROM TABLE
WHERE DATEPART(wk, TABLE.DATECOLUMN) 
        = DATEPART(wk, (SELECT DATECOLUMN FROM TABLE WHERE ID = GivenID))
    AND DATEPART(yy, TABLE.DATECOLUMN) = DATEPART(yy, (SELECT DATECOLUMN FROM TABLE WHERE   ID = GivenID))

UPDATE FOR SQLITE

To do this in SQLLite, Refer to this SO question and then this article that states %W is what you use to get week and %Y for year. Which gives you:

SELECT * 
FROM TABLE
WHERE STRFTIME('%W', TABLE.DATECOLUMN) 
        = STRFTIME('%W', (SELECT DATECOLUMN FROM TABLE WHERE ID = GivenID))
    AND STRFTIME('%Y', TABLE.DATECOLUMN) 
        = STRFTIME('%Y', (SELECT DATECOLUMN FROM TABLE WHERE ID = GivenID))