Question

I have the following two tables:

TABLE: area
*City_ID   *Number   Name
--------   -------   ----
SUR        1         Fleetwood
SUR        2         Whalley
SUR        3         Guildford
SUR        4         Newton
SUR        5         Cloverdale
SUR        6         South Surrey
ABB        1         Abbotsford East
ABB        2         Abbotsford West
ABB        3         Aberdeen
ABB        4         Bradner
ABB        5         Central Abbotsford
ABB        6         Matsqui
ABB        7         Poplar
ABB        8         Sumas Mountain
ABB        9         Sumas Prairie

TABLE: city
*ID        Name
---        ----
SUR        Surrey
ABB        Abbotsford
LAN        Langley

Using the following statement:

SELECT DISTINCT area.City_ID, city.Name
FROM area
INNER JOIN city
WHERE area.City_ID = city.ID

I get:

SELECT:
City_ID    city.Name
-------    ---------
SUR        Surrey
ABB        Abbotsford

But how do I SELECT the following:

SELECT:
City_ID    city.Name    area_COUNT
-------    ---------    ----------
SUR        Surrey       6
ABB        Abbotsford   9

where area_COUNT is the number of rows in area for each corresponding City_ID?

Answer 1

Use GROUP BY instead of DISTINCT:

SELECT city.City_ID, city.Name, COUNT(*)
FROM area
INNER JOIN city
WHERE area.City_ID = city.ID
GROUP BY city.ID