Questions tagged [subquery]
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.
716 questions
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Assistance with MySQL query
I have following tables
Tags
id | tag_name | slug |
1 | tag1 |tag1
2 | tag1 |tag1
products
id | proudct_name
1|product1
2|product2
product_tags
id | product_id | tag_id
1|1||1
2|1|2
3|2|1
i ...
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MySQL query to reference previous field in subqueries
I have a question on how to best do this.
I have a table that contains how users are enrolled in a class, say "manual", "db", "email", etc. (enrolment type).
each class has a list of their own class ...
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571
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How to perform query operation on another query result
How to get approved , unapproved , deleted count from the below result using sql query.
SELECT approved,deleted_at,count(id)AS count FROM `payment_voucher`
WHERE company_id = 1 GROUP BY approved,...
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1
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924
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Distinct result with row_id for limit query
There are 2 tables:
CREATE TABLE sample1 (
id int,
name varchar,
score int,
mode int
)
CREATE TABLE sample2 (
id int,
mode int
...
)
I need to select distinct name with MIN(score) and ...
- 113
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1
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postgres subquery uses ungrouped column
I have a query in which I am trying to add a column which contains a percentage of records which have a certain value versus the total number of records. I can get the subquery to work on its own, but ...
- 115
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2
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3k
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Locate multiple duplicate columns in PostgreSQL table
I am trying to report on duplicate records in a single table which has a unique key of app_cao_number. The duplicates occur if either: 1. The Passport field is duplicated; 2. The ID field is ...
- 137
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2
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How to get sum of 3 sub count queries and group them using an attribute
I have 3 queries as follows:
For the date 2019-12-02, I am calculating 3 type of values. The total value for 2019-12-02 must be the sum of these 3 queries.
Q1
SELECT count(*)
FROM ...
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2
answers
959
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Column not like any value in column in other table - function
The two tables in question are:
completed_types
id | type
---|--------
1 | XXX
2 | YYY
all_types:
id | type | sub_type
---|-------|---------
1 | XXX X | aaa
2 | XXX-Y | bbb
3 | YYY-X | ccc
4 ...
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2
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2
answers
1k
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Postgresql expanding view multiple times instead of executing it once
I have a rahter long subquery which I store as a view
CREATE VIEW scans_minmax AS
SELECT tmp.source,
value ->> 'Ok' AS "Ok",
...
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462
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select subquery condition in where statement
I am getting this error:
ORA-06550: line 43, column 16: ORA-00904: "STOCK_BALANCE": invalid identifier
...for the following query:
select PARTY_ID,
PARTY_NAME,
IT_ID,
IT_ID ||...
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651
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Ordering by field, constructed by subquery is slow
My tables (oversimplified for clarity):
documents: registrations:
|id| |id|document_id|date|
My simplified query:
SELECT *
FROM (SELECT documents.*,
(SELECT max(date)
...
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1
answer
3k
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Calculating percentage over sub query SQL
I have a table that records events regarding email campaigns. I want to figure out the percentage of campaigns where there was more than one event happening for the campaign.
First I calculated the ...
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Query with a few subqueries and appropriate indicies taking, on average, 613ms to execute
I have a ton of queries that do a similar thing as to what I'm doing here, but none of them have the performance issues this one does:
SELECT
(SELECT lead_id FROM leads WHERE to_id = lead_id OR ...
- 147
-1
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1
answer
2k
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Aggregate function on subquery
I have got a SALES table that has 4 document types, and they are created with reference to each other in the following order:
Offer -> Order -> Delivery -> Invoice.
For each new row their ...
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2
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0
answers
391
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adding results of InfluxDB subqueries
I'm trying to get the kWh from multiple entities in InfluxDB in Grafana. I have the following raw query.
SELECT ("a" + "b") / 3600000 FROM (
SELECT spread("watt_seconds") AS "a" FROM "W"
...
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1
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4k
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Replace long GROUP BY list with a subquery
This is a repost of my question on Stack Overflow. They suggested to ask it here:
I found an online article from 2005, where the author claims, that many devs use GROUP BY wrong, and that you should ...
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1
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4k
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Sub Query with group by returns more than 1 row Issue
I am facing the issue of subquery returns more than 1 row cause I am using group by in the subquery and outer query both to get the desired result.
This is my query
SELECT Count(*) ...
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1
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80
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optimize query -- remove nested selects
How can I rewrite the query to increase performance?
Here is the query:
SELECT flight.*,
DAYOFWEEK(flight.flight_time) AS day_of_week,
IF(SUM(...
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1
answer
19k
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There is a column named in table but it cannot be referenced from this part of the query
I've been learning Postgres (coming from SQL Server), and this error really confuses me.
Here is the code with some sample data:
create table T (
ID serial primary key,
A varchar(1),
B varchar(1),
C ...
- 1,223
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41
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Need help with correlated subquery
I have two PostgreSQL tables that each contain a column called date_of_incident.
They each also have a column called incident_id and this is how the tables are related.
I want to update all rows of ...
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answers
204
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Can subqueries produce different execution plans than CTE's?
I was talking with the bossman, and he prefers subqueries over CTE's. Personally, I loathe subqueries. He mentioned that subqueries can be faster, but I am not convinced. I ran this short test:
...
- 2,650
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Select/print data from subquery
In my application I have a table "user", a table "role", and a table "userroles". Userroles is simple table consisting of user, role, where user corresponds to the id column of the user table. As user ...
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2k
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Optimize slow COUNT in MySQL subquery
I have the following query that takes minutes to complete:
SELECT DISTINCT Designation, Model, (
SELECT COUNT( Equipment.EquipmentID )
FROM Equipment
INNER JOIN EquipmentDesignation_Vw ...
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-2
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3
answers
1k
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Can a `Select` Subquery be conditionally returned? [closed]
Is it possible in Postgres to return a column(Resulting from a subquery) only when a condition matches?
Query:
SELECT
(SELECT NOW()) AS FIRST,
(SELECT NOW()) AS SECOND
Outputs:
| first | ...
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1
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1k
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Postgres Pass Subquery results to function that returns TABLE
I have a function that accepts arrays as parameters and returns a table. I can get the arguments passed in correctly, but it is returning rows of type record. If I try to expand the record with FROM I ...
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1
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1k
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Is there a way to alias columns for reference in subqueries?
I have a SQL statement in PostgreSQL that takes the following form:
SELECT * FROM db WHERE (b + 1) IN (SELECT b FROM db WHERE a = 7)
This query returns each record whose b value, incremented by 1, ...
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How to rank an aggregation in each newly formed group?
The problem below that I would like to solve sounds quite simple but it is quite difficult for me to arrive at the solution with SQL.
Let's say I have a simplified ERD that looks as follows:
This ...
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98
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How to get column values in where condition in sub query? [closed]
I am trying to get distinct list of values in where condition through sub query but it shows 0 rows in result set. Here is my query.
SELECT a.topic_id, t.id as topicid, t.value as value, t.topic as ...
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601
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How to use query result as REPLACE parameters
i'm trying to:
1- Find a string inside a lot of content
2- Replace that specific part of the string with a new one using REPLACE function like this:
REPLACE(column_name, query#1, query#2)
Is this ...
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2k
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Query to get the physical file name of the database
Im trying to get the physical file name of a database, and when i query sys.database_files, under the physical file name column, you get the whole path (ie. S:\Program Files\Microsoft SQL Server\...
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Postresql using subquery select in order by clause
Is it possible to order by a selected columnname?
SELECT * FROM tablex ORDER BY quote_ident((
select column_name from information_schema.columns
where table_name = tablex AND column_name LIKE '...
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1k
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Subquery caching in join
I have very complex MySQL queries that use the same subquery over and over again. I was wondering if MySQL will run the subquery multiple times or use the previous resultset. Is there any way to tell ...
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48
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selecting data after filtering out
I am using RDBMS MySQL 5.7. I have 3 tables with the following structures:
Table A - primary table - products:
+----+-----------+-------------+------------+--------+
| id | title | description |...
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Finding matching sub values?
So not too sure how to go about this, but ideally I want to pull out matching & non-matching info from an array of rows in a table, so I have a table with info like this:
12,2019-07-15 06:02:52,...
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199
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Problem with How to join with subquery
I'm trying to create a report in Postgresql that shows some columns from some tables with join. But one of them is subquery that to show a customer with the location. My Problem is, I always get ...
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Why last table don't using index for joining?
By the help of others members i get an Query idea for my previous problem. But after writing this, the EXPLAIN showing that my last table do't using index for join but the joining ROW is PRIMARY KEY, ...
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Sql subquery for nested parent child data
I have two tables , on parent table (categories ) and child table (features).. I have this query
select c.* ,
(select GROUP_CONCAT(f.featuresId , f.featuresTitle )
from ...
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1
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39
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MySQL - Optimize subquery in Select, where and order by
Im running a query like below.
SELECT DISTINCT c.`id`
, c.`job-cat`
, (
SELECT COUNT(*)
FROM `jobs` j
WHERE j.`mul_category` IN (c.`id`)
AND j.`ending` >...
- 1,960
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2
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693
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Postgres select using lateral
I'm after running a query with a subquery (perhaps inefficient) that using a regular expression pattern it can return how many instances of a characters are included with a given record.
In doing so, ...
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Query to Find Multiple Start Time and End Time on a Single Day based on Boolean Value
I want to find the multiple Start Time and End time in a single Day based on the Boolean value where data is divided into each half hour interval for a day. So Each day is divided into 24hrs/2 = 48. ...
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How do I create a table with count of instances of an id before an event date that is individual to that id?
I am very new to SQL and have a relatively complex query to write, any help would be appreciated.
I have data with the following columns:
ORDER_ID
CUST_ID
ORDER_DATE
RETURNED(1/0)
I need a table ...
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45
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Slecting specific query returnned data related records from another table [closed]
Product table:
productId | productName | unitPrice | supplierId
_______________________________________________
1 | Iphone8 | 1500 | 3
2 | Nokia 6 | 800 | 1
...
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1
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10k
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How to take make OFFSET & LIMIT with COUNT (OVER?) when having a subquery?
It appears I have a case I can't quite wrap my brains around. So coming here in hopes to find pointers to a query that maybe could be helpful to someone else too.
In the following, I have a query ...
- 279
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votes
2
answers
29k
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Limit left join for multiple rows
Since MySql doesn't support main alias reference in subquery is a bit challenging to create query with multiple rows where you have to limit rows of left join tables.
Let's overview simple example.
...
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47
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Two aggregated sub queries wont run
I am having trouble with the below, I need to average two columns in a correlated subquery and I cannot get it to work, how do i get both aggregate sub queries to run then go through the outer query? ...
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2
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75
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What am I doing wrong with subquery
I cannot work this out, how do I get the subquery to return the lowest course weight for each lecturer, it currently only returns the lowest and is my subquery wrong or outer query?
Question: Show ...
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2k
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Why is an empty rowset not equivalent to null when assigning a query result to a variable and how best to work around?
I have a cursor. Within my loop I select a single column and assign the result to a variable. When the select returns an empty rowset, nothing is assigned to the variable. In particular, the variable ...
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145
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Cannot get a user function to co-operate with a subquery in mariadb
The following is a demo of an issue we are having with a function and a subquery. I'm interested to know if it is a bug or if there is a reasonable explaination why it is failing.
Notes:
Problem ...
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2k
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Having a subquery somehow do the same group by as the outer query
i'm pretty decent with SQL but it's not my main experience of expertise. A colleague asked me a stumper of a question the other day. I was wondering if you guys could provide assistance.
Basically we'...
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3
answers
8k
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Return ALL rows based on a matching date also matching a specific value in another column
I'm using SQL Server 2014, exact version: 12.0.5579.0.
I've tried a subquery under a SELECT and WHERE statement and it brings back false results with rows of any row with a 1/1/2019 date. It just ...
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