Grouping by all non-aggregated columns in MSSQL - sql

Question

Suppose I have two tables PO and PO_Line and I want to list all fields from PO plus the quantity of rows from PO_Line that link back to each row in PO I would write a query something like -
SELECT
PO.propA,
PO.propB,
PO.propC,
PO.propD,
PO.propE,
...
PO.propY,
COUNT(PO_Line.propA) LINES
FROM
PO
LEFT JOIN
PO_Lines
ON
PO.ID = PO_Lines.PO_ID
Obviously this would give an error someting along the lines of -
Column 'PO.propA' is invaalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.
So to get the query to run I will add a GROUP BY clause to the end of the query and copy and paste my select lines, like so -
SELECT
PO.propA,
PO.propB,
PO.propC,
PO.propD,
PO.propE,
...
PO.propY,
COUNT(PO_Line.propA) LINES
FROM
PO
LEFT JOIN
PO_Lines
ON
PO.ID = PO_Lines.PO_ID
GROUP BY
PO.propA,
PO.propB,
PO.propC,
PO.propD,
PO.propE,
...
PO.propY
Which works perfectly however it all feels a little unwieldy, especially if I've named my columns i.e. -
SELECT
PO.propA AS 'FIRST PROPERTY',
PO.propB AS 'SECOND PROPERTY',
PO.propC AS 'THIRD PROPERTY',
PO.propD AS 'ANOTHER PROPERTY',
PO.propE AS 'YOU GET THE IDEA',
...
PO.propY
and I have to copy/paste the entries from the select clause and then delete the column names.
So my question is - Is there a shorthand method to say group by all non-aggregated entries found in the select clause?

Answer 1

I think you just want window functions:
SELECT . . .,
COUNT(PO_Line.propA) OVER (PARTITION BY PO.ID) as LINES
FROM PO LEFT JOIN
PO_Lines
ON PO.ID = PO_Lines.PO_ID;

Answer 2

I have to copy/paste the entries from the select clause and then delete the column names.
I strongly suggest to use block/column selection.Move , as first element and allign your aliases:
SELECT
PO.propA AS 'FIRST PROPERTY'
,PO.propB AS 'SECOND PROPERTY'
,PO.propC AS 'THIRD PROPERTY'
,PO.propD AS 'ANOTHER PROPERTY'
,PO.propE AS 'YOU GET THE IDEA'
...
,PO.propY
,COUNT(PO_Line.propA) LINES
FROM PO
LEFT JOIN PO_Lines
ON PO.ID = PO_Lines.PO_ID
GROUP BY
...
In SQL Server Management Studio use simple block selection SHIFT + ALT highlight and paste.
If you are using other editor find corresponding keyshortcut here.
It is nice for multiple edit at once like adding schema, alias, ...and so on.

Answer 3

Reading your query I think you might not need a GROUP BY to begin with:
SELECT
PO.propA,
PO.propB,
PO.propC,
PO.propD,
PO.propE,
...
PO.propY,
(SELECT COUNT(*) FROM PO_Lines WHERE PO.ID = PO_Lines.PO_ID) LINES
FROM
PO