SQL term used to describe when a `SELECT` statement is used as part of a larger SQL statement. The larger statement may be DML and is always found within brackets or parenthesis.

learn more… | top users | synonyms

3
votes
3answers
3k views

Query to find GUID's “not in” null containing subquery returns no results

When I have a query that checks if a column of type uniqueidentifer does not exist in a table that has a null value then I get no results back. If the subquery does not return a null it works fine and ...
2
votes
3answers
3k views

SQL Subquery , One to Multiple rows

Following query I have written returns the result as expected, example 121350 rows. SELECT dbo.Articles_in_Consignment.Consignment_id, dbo.ORDER_D.Orders_boxsize, ...
3
votes
1answer
129 views

Subquery magic in PostgreSQL

I have a query: update product_product set (write_date, default_code) = (LOCALTIMESTAMP, 'update') where product_tmpl_id in ( select distinct product_tmpl_id from product_template ...
3
votes
1answer
8k views

Writing a query to find all employee salaries that are higher than their managers

I have two tables with some dummy data. I need to find all employees that make more than their managers. I was led to believe the point of the exercise is to learn how to do subqueries. I can isolate ...
3
votes
5answers
682 views

Query optimization [Oracle]

The Query: select JOIN_RESULT.batch_id as BATCH_ID, JOIN_RESULT.unique_doc_id as DOCUMENT_ID, JOIN_RESULT.brand as BRAND, JOIN_RESULT.message_date_time as UPLOAD_DATE, ...
12
votes
1answer
395 views

Why does subquery use parallelism and join doesn't?

Why does SQL server use parallelism when running this query which uses a subquery but it doesn't when using a join? The join version runs in serial and takes around 30 times longer to complete. Join ...
5
votes
1answer
2k views

Mysql sub query returns more than 1 row

SELECT * FROM wp_posts WHERE ID IN ( (SELECT courses FROM wp_category WHERE CatID =401) OR (SELECT meta_value FROM wp_postmeta WHERE post_id IN (SELECT courses FROM wp_category WHERE CatID =401) ...
5
votes
2answers
2k views

Is there a way to hint to query optimizer to MySQL which constraints should be done first?

This is my current query: SELECT BusinessID as ID, 111151.29341326*SQRT(pow(-6.186751-X(LatLong),2)+pow(106.772835-Y(LatLong),2)*0.98838574205337) AS Distance from ( SELECT * FROM ...
4
votes
2answers
81 views

How can i return the max of a sum by each team?

I have a lot of teams and i want to know the maximum of sum total of each team. This's my query : SELECT campaign_id, campaign_identifier, team, campaign_name, ...
3
votes
3answers
892 views

No advantage of using Cross Apply or CTE over inline sub-query

I came across a query like this: SELECT (SELECT COUNT(1) FROM Orders o WHERE i.ItemId = o.ItemId) [C] FROM Items i I changed it to following ;WITH cte_count AS ( SELECT COUNT(1) c, OrderId ...
2
votes
1answer
2k views

Best practice: Unions or a derived table?

I've inherited a medium-sized database with a terrible schema. The sanitized portion in question is like so: CREATE TABLE `pending` ( ... `invoice` int(11) DEFAULT NULL, `lid` int(11) DEFAULT ...
2
votes
2answers
2k views

Why do I need to use a sub query to filter down a grouped select?

If I do this -- SELECT dv.Name ,MAX(hb.[DateEntered]) as DE FROM [Devices] as dv INNER JOIN [Heartbeats] as hb ON hb.DeviceID = dv.ID WHERE DE < '2013-03-04' GROUP BY dv.Name ...
1
vote
2answers
153 views

Use array expression from subquery in ANY() condition

I have a relatively complicated query with a subquery fetching an array like so: ... ARRAY(SELECT category_id FROM category_schedule_con con WHERE s.id = con.schedule_id ORDER BY category_id) ...
1
vote
1answer
135 views

Postgres Nested WHEN Aggregate Function

In PostgreSQL (version 9.4) I am trying to construct a query to determine in various tranches how many times various numbers appear in the data set between ranges. When I query group-ing by ...
1
vote
1answer
10k views

Delete from table where multiple fields match select subquery from other table

I want to delete an entry in a table where multiple fields match the results of another select subquery which takes data from another table. This is what I have so far, though it doesn't work: ...