Counts on Date Range and Individual Days - sql-server

Question

I'm having to re-write a project that was done using a combination of SQL queries and Query-of-Queries in ColdFusion. There were dozens of queries referencing the original SQL Query results set, but it wasn't abstracted to work for different events. So I would like to improve it by moving most of the counting into SQL. I got the first 6 counts they need working (not sure if in the most optimal way). But, in addition to those, I need to be able to do a break down not just on the overall date range, but also for each individual day in that date range for the unique counts.
So far the query is:
SELECT Count(CASE
WHEN type IN ( 1, 3, 4, 5, 9 ) THEN barcode
ELSE NULL
END) AS total_scans,
Count(CASE
WHEN type IN ( 2, 8 ) THEN barcode
ELSE NULL
END) AS total_creds,
Count(barcode) AS total_scans,
Count(DISTINCT CASE
WHEN type IN ( 1, 3, 4, 5, 9 ) THEN barcode
ELSE NULL
END) AS unique_scans,
Count(DISTINCT CASE
WHEN type IN ( 2, 8 ) THEN barcode
ELSE NULL
END) AS unique_creds,
Count(DISTINCT barcode) AS unique_scans
FROM (SELECT c.id,
a.barcode,
d.type,
c.location,
Datepart(mm, a.scan_time) AS scan_month,
Datepart(dd, a.scan_time) AS scan_day,
Datepart(hour, a.scan_time) AS scan_hour,
Datepart(minute, a.scan_time) AS scan_min
FROM [scan_11pc_gate_entries] AS a
INNER JOIN scan_units AS b
ON a.scanner = b.id
INNER JOIN scan_gates AS c
ON b.gate = c.id
INNER JOIN [scan_11pc_gate_allbarcodes] AS d
ON a.barcode = d.barcode
WHERE ( c.id IN (SELECT id
FROM scan_gates
WHERE ( event_id = 21 )) )
AND ( a.valid IN ( 1, 8 ) )
AND a.scan_time >= '20110808'
AND a.scan_time <= '20110814') data

Answer 1

Well I see plenty of other room for improvement / optimization here, but to satisfy the immediate requirement:
SELECT d, Count(CASE WHEN type IN ( 1, 3, 4, 5, 9 ) THEN barcode
ELSE NULL END) AS total_scans,
Count(CASE WHEN type IN ( 2, 8 ) THEN barcode
ELSE NULL END) AS total_creds,
Count(barcode) AS total_scans,
Count(DISTINCT CASE WHEN type IN ( 1, 3, 4, 5, 9 ) THEN barcode
ELSE NULL END) AS unique_scans,
Count(DISTINCT CASE WHEN type IN ( 2, 8 ) THEN barcode
ELSE NULL END) AS unique_creds,
Count(DISTINCT barcode) AS unique_scans
FROM (SELECT c.id, -- is this column necessary?
a.barcode,
d.type,
c.location, -- is this column necessary?
d = DATEADD(DAY, DATEDIFF(DAY, 0, a.scan_time), 0)
FROM [scan_11pc_gate_entries] AS a
INNER JOIN scan_units AS b
ON a.scanner = b.id
INNER JOIN scan_gates AS c
ON b.gate = c.id
AND c.event_id = 21 -- join criteria,
-- shouldn't be an extra IN clause
INNER JOIN [scan_11pc_gate_allbarcodes] AS d
ON a.barcode = d.barcode
WHERE ( a.valid IN ( 1, 8 ) )
AND a.scan_time >= '20110808'
AND a.scan_time <= '20110814') data
GROUP BY d
ORDER BY d;
Note that >= and <= is the same as BETWEEN, and unless scan_time is a DATE column (or guaranteed to always be at midnight), the approach you're using isn't safe. Better to say:
AND a.scan_time >= '20110808'
AND a.scan_time < '20110815'
More info here:
What do BETWEEN and the devil have in common?
EDIT
Understanding that this is based on the information I've pieced together from comments and questions, which is far from a complete picture of your environment and workload, an indexed view you may find useful would be:
CREATE VIEW dbo.myview
WITH SCHEMABINDING
AS
SELECT c.event_id,
a.barcode,
[type] = CASE WHEN d.[type] IN (2,8) THEN 'c' ELSE 's' END,
scan_date = DATEADD(DAY, DATEDIFF(DAY, 0, a.scan_time), 0),
total = COUNT_BIG(*)
FROM dbo.scan_11pc_gate_entries AS a
INNER JOIN dbo.can_units AS b
ON a.scanner = b.id
INNER JOIN dbo.scan_gates AS c
ON b.gate = c.id
INNER JOIN dbo.scan_11pc_gate_allbarcodes AS d
ON a.barcode = d.barcode
WHERE (a.valid IN (1,8))
AND d.[type] IN (2,3,4,5,8,9)
GROUP BY
c.event_id,
a.barcode,
CASE WHEN d.[type] IN (2,8) THEN 'c' ELSE 's' END,
DATEADD(DAY, DATEDIFF(DAY, 0, a.scan_time), 0);
GO
CREATE UNIQUE CLUSTERED INDEX x
ON dbo.myview(event_id, barcode, [type], scan_date);
Now you can write a query that does something like this:
SELECT [date] = CONVERT(CHAR(8), scan_date, 112),
SUM(CASE WHEN [type] = 's' THEN total ELSE 0 END) AS total_scans,
SUM(CASE WHEN [type] = 'c' THEN total ELSE 0 END) AS total_creds,
COUNT(CASE WHEN [type] = 's' THEN 1 END) AS unique_scans,
COUNT(CASE WHEN [type] = 'c' THEN 1 END) AS unique_creds
FROM dbo.myview WITH (NOEXPAND) -- in case STD Edition
WHERE event_id = 21
AND scan_date BETWEEN '20110808' AND '20110814'
GROUP BY scan_date
UNION ALL
SELECT [date] = 'weekly',
SUM(CASE WHEN [type] = 's' THEN total ELSE 0 END) AS total_scans,
SUM(CASE WHEN [type] = 'c' THEN total ELSE 0 END) AS total_creds,
COUNT(DISTINCT CASE WHEN [type] = 's' THEN barcode END) AS unique_scans,
COUNT(DISTINCT CASE WHEN [type] = 'c' THEN barcode END) AS unique_creds
FROM dbo.myview WITH (NOEXPAND) -- in case STD Edition
WHERE event_id = 21
AND scan_date BETWEEN '20110808' AND '20110814'
ORDER BY [date];
This is all completely untested as your schema is a little bit cumbersome to try and create a complete repro of your system, but hopefully this gives you a general idea to work from...