SQL: See how many items in a list, return a hit in a table (using LIKE) - sql

Question

For the sake of argument, say I'm looking for first names in a table. And, the table is irregular - no pattern, some people have 2 names, some 3, some it's all run together, whatever.
SELECT
COUNT(*)
FROM
NAME_TABLE N
WHERE
--the list
N.NAME LIKE 'John%'
OR N.NAME LIKE 'Mich%'
OR N.NAME LIKE 'Rob%'
The above would give how many hits - maybe 70 or 70000, who knows. But, what I really want is a response from 0-3.
i.e., how many of my search terms, get a hit in the table.
I could just run the query and pull the entire table of hits, then
use Excel to get the answer.
Or if in a more typical programming language, I could run a loop
that has an x + 1 in it.
But is there a way to do this directly in an SQL query? Specifically T-SQL I guess...very specifically SQL Server 2008, but I'm kinda curious in general.

Answer 1

Your question is not very clear, at least for me, but my magic crystall ball tells me, that eventually you are looking for something like this:
USE master;
GO
SELECT SUM(CASE WHEN PATINDEX('sys%',[name])>0 THEN 1 ELSE 0 END) AS CountOfSys
,SUM(CASE WHEN PATINDEX('plan%',[name])>0 THEN 1 ELSE 0 END) AS CountOfPlan
,SUM(CASE WHEN PATINDEX('spt_%',[name])>0 THEN 1 ELSE 0 END) AS CountOfSpt
FROM sys.objects;
Another approach was to do a
SELECT 'sys%' AS Pattern, COUNT(*) AS CountPattern
FROM ... WHERE [name] LIKE 'sys%'
UNION ALL
SELECT 'plan%',COUNT(*)
...
UNION ALL
...
This would return a list of all your counts in tabular form.
The third chance was to place all your search patterns into a table and use this table in a CROSS JOIN (similar idea then the UNION approach, but more flexible and more generic):
USE master;
GO
DECLARE #tblPattern TABLE(Pattern VARCHAR(100));
INSERT INTO #tblPattern VALUES('sys%'),('plan%'),('spt_%');
SELECT p.Pattern
,SUM(CASE WHEN PATINDEX(p.Pattern,o.[name])>0 THEN 1 ELSE 0 END) AS CountPattern
FROM sys.objects AS o
CROSS JOIN #tblPattern AS p
GROUP BY p.Pattern

Answer 2

You can use a case statement for each name that resolves to 1 if the name exists in the table or 0 if it does not. Then just add them together and the result will be 0-3 i.e. the number of names that exist in the table.
select
case when exists
select 1 from name_table
where name like 'John%'
then 1 else 0 end
+
case when exists
select 1 from name_table
where name like 'Mich%'
then 1 else 0 end
+
case when exists
select 1 from name_table
where name like 'Rob%'
then 1 else 0 end