SQL Server, fetching data from multiple joined tables. Why is slow?
- by user562192
I have problem with performance when retrieving data from SQL Server.
My sql query looks something like this:
SELECT
table_1.id,
table_1.value,
table_2.id,
table_2.value,...,
table_20.id,
table_20.value
From table_1
INNER JOIN table_2
ON table_1.id = table_2.table_1_id
INNER JOIN table_3
ON table_2.id = table_3.table_2_id...
WHERE table_1.row_number BETWEEN 1 AND 20
So, I am fetching 20 results.
This query takes about 5 seconds to execute.
When I select only table_1.id, it returns results instantly.
Because of that, I guess that problem is not in JOINs, it is in retrieving data from multiple tables.
Any suggestions how I would speed up this query?
