In article <[EMAIL PROTECTED]>,
John Mistler <[EMAIL PROTECTED]> writes:
> Good idea. liang le's answer almost got it, but I couldn't make it work
> with string values quite right. Here is my situation:
> I am issuing a series of queries all-in-one like "SELECT nameColumn,
> otherColumn FROM theDatabase WHERE rowID = 1;SELECT nameColumn, otherColumn
> FROM theDatabase WHERE rowID = 2;SELECT nameColumn, otherColumn FROM
> theDatabase WHERE rowID = 3;"
> expecting a return of
> aName otherItem
> aName otherItem
> aName otherItem
> but if one of those rowIDs does not exist, then I get
> aName otherItem
> aName otherItem
> and my app has no value for the non-existing row. I would like for the
> query to return an indication that the row did not exist, like:
> aName otherItem
> 0 or '' or 'NULL' (no nameColumn entries will ever = 0, or '', or NULL)
> aName otherItem
> Does that make more sense, and if so, is there a solution?
This sounds like a broken DB design. You should have another table
listing all possible rowIDs; something like that:
CREATE TABLE myRows (
rowID INT NOT NULL,
nameColumn VARCHAR(255) NOT NULL,
PRIMARY KEY (rowID)
);
INSERT INTO myRows (1, 'row #1');
INSERT INTO myRows (2, 'row #2');
INSERT INTO myRows (3, 'row #3');
Then you can do the following:
SELECT t1.nameColumn, coalesce(t2.otherColumn, '')
FROM myRows t1
LEFT JOIN yourTable t2 ON t2.rowID = t1.rowID
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