Using JOIN statement with CONTAINS function - sql-server

Question

In SQL Server database I have a View with a lot of INNER JOINs statements. The last join uses LIKE predicate and that's why it's working too slowly. The query looks like :
SELECT *
FROM A INNER JOIN
B ON A.ID = B.ID INNER JOIN
C ON C.ID1 = B.ID1 INNER JOIN
...........................
X ON X.Name LIKE '%' + W.Name + '%' AND
LIKE '%' + W.Name2 + '%' AND
LIKE '%' + W.Name3 + '%'
I want to use CONTAINS instead of LIKE as :
SELECT *
FROM A INNER JOIN
B ON A.ID = B.ID INNER JOIN
C ON C.ID1 = B.ID1 INNER JOIN
...........................
X ON CONTAINS(X.Name, W.Name) AND
CONTAINS(X.Name, W.Name2) AND
CONTAINS(X.Name, W.Name3)
I know that CONTAINS is working faster than LIKE and also that can't use CONTAINS in JOIN statements.
Is there any workaround in this case or suggestion?
Thanks in advance.

Answer 1

It's not that CONTAINS can't be used in joins.
You just can't use columns as a second parameter of CONTAINS - see MSDN - CONTAINS (Transact-SQL)
CONTAINS
( { column_name | ( column_list ) | * }
,'<contains_search_condition>'
[ , LANGUAGE language_term ]
)
However, you can use a variable as a search condition, so you can use a cursor and then get all data you need.
Here is some very rough example:
declare #Name nvarchar(max)
declare #Temp_A table(Name nvarchar(max))
declare #Temp_B table(Name nvarchar(max))
--=============================================================================================
insert into #Temp_A (Name)
select 'Test'
insert into #Temp_B (Name)
select 'aaaTestaaa'
--=============================================================================================
-- Query 1 - LIKE
--=============================================================================================
select *
from #Temp_A as A
inner join #Temp_B as B on B.Name like '%' + A.Name + '%'
--=============================================================================================
-- Query 2 - CONTAINS
--=============================================================================================
declare table_cursor cursor local fast_forward for
select distinct Name from #Temp_A
open table_cursor
while 1 = 1
begin
fetch table_cursor into #Name
if ##fetch_status <> 0 break
select * from #Temp_B where contains(Name, #Name)
end
close table_cursor
deallocate table_cursor

Answer 2

CONCAT works perfect, I have tested it with PostgreSQL
SELECT *
FROM TABLE_ONE AS a INNER JOIN TABLE_TWO AS b
ON b.field LIKE CONCAT('%', CONCAT(a.field, '%'));
Please refer to similar answer here

Answer 3

You can create a join using a LIKE..
something like this:
SELECT * FROM TABLE_ONE
FULL OUTER JOIN TABLE_TWO ON TABLE_ONE.String_Column LIKE '%' + TABLE_TWO.Name + '%'
ie - select everything from TABLE_ONE where the string_column is contained in the TABLE_TWO name

Answer 4

In short there isn't a way to do this using CONTAINS, it simply is not allowed in a JOIN like this.
see: TSQL - A join using full-text CONTAINS
So although there is performance hit, IMO like is the easiest solution here.