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Get difference in values of second table from IDs in two columns of first table?

Given these two tables: Table1 id1 id2 224 2341 5234 9394 6243 2342 ⋮ ⋮ Table2 id value 224 2 2341 52 2342 24 5234 23 6243 242 9394 99 ⋮ ⋮ I would like to create this table: Table3 id1 ...
Geremia's user avatar
  • 103
0 votes
1 answer
33 views

How to Do a Sub Query and JOIN for Comparison Report

Hi I was trying to do a Sub Query and Comparison Report For Example, I have a Table of Teams with Color AND Name in a Single Table. A person can be on more than one Team and Multiple Team Colors can ...
user1207381's user avatar
1 vote
1 answer
38 views

MySQL Tennis Ladder View Creation Question

I am creating a Tennis Ladder VIEW using MySQL and wish to do the following: Properly create a view that includes: All player's names These player names will come from the table: User - using the ...
Reno Kendo's user avatar
-3 votes
1 answer
130 views

subquery vs join which is better [closed]

SELECT * FROM table1 WHERE t2id in ( SELECT id FROM table2 WHERE t3id = (SELECT id FROM table3 WHERE id = '1') ); SELECT * ...
guradio's user avatar
  • 97
1 vote
1 answer
162 views

Combining Multiple queries from the same table inrto 1 query

I am looking to find a way to achieve the below... I have tried using Joins and SubQueries but no joy as yet... I have a table that keeps track of wins/loses/draws as so Date WLD 01/01/23 Win 05/01/...
Paulmcf1987's user avatar
0 votes
2 answers
57 views

I have a database with a player, tournament, and registration table. I need to query all players that played in 2 types (attributes) of tournaments

I currently have two tournaments that have matches. Wimbledon and Atlanta open which I have one as a grand slam and the other as a masters 1000, and I want to get the players who played in both This ...
zaria palmer's user avatar
-2 votes
1 answer
24 views

Extracting data from two tables

I have( for example) a table called A and a table called B. Table A contains tons of user data( age, country bla bla) and is connected to B by forein_key=id( B only has ID/NAME. I want to find out how ...
Gal Mor's user avatar
0 votes
2 answers
2k views

How to Select The Lowest Date in one field that's higher than the date in another field

The below aim isn't actually what my query is for, but I'm using it as an analogy to explain more simply what I am trying to achieve: I am trying to build a BigQuery Script which looks at all arcade ...
Phil Tomlinson's user avatar
0 votes
1 answer
480 views

MySQL query: Detect different rows between two tables and show differences in result table

I have two tables in a MySQL database. Table1 a_id 1 3 4 5 6 Table2 b_id 1 2 3 I would like to spot the missing row from Table1 a_id 2, and missing rows from Table2 b_id 4,5,6, which should be shown ...
klor's user avatar
  • 157
-1 votes
1 answer
2k views

Optimize 5 million records SQL query (use join or not?!)

I have a table for products that contains almost 5 million records. I have a column for the product category (product_category). That it is for now of type INT(11) and it is an index and refers to ...
Ahmed Moayad AlMoghrabi's user avatar
1 vote
1 answer
1k views

How do I SELECT elements using WHERE with another table's record values in WHERE statement?

Problem summary Today part of my app crashed, but nothing else stopped with it. I need to find the first and last tracked message ids for each channel during the downtime. I log unix timestamps ...
jayc331's user avatar
  • 13
1 vote
0 answers
457 views

Postgres: one-to-one join with duplicates and inequality matching

** Update: Fiddles now included https://dbfiddle.uk/?rdbms=postgres_14&fiddle=0c618e64c7fcd54c8781ed7d1ac540f0 and https://sqlfiddle.com/#!17/12053 ** I have two tables taken from two data sources,...
Harry E.'s user avatar
1 vote
1 answer
2k views

How do I get the sum of a field and avoid duplication from an inner join?

I am pulling Geo from the Accounts table and I am ranking the Geos by Opportunity $$ Amt based on Accounts that have the name like "Brinks%". Accounts are unique, and there can be many ...
Liz's user avatar
  • 13
-1 votes
1 answer
4k views

SQL query to join on maximum value on a per-row basis

I'm stuck writing a query for the following scenario: I have a table of things, they have a metric called number in the examples below. I have another table called offers which is a list of offers ...
RDD Brian's user avatar
0 votes
1 answer
770 views

Understanding why getting each parent row joined with its latest child is not working when using subquery filter

I have a parent-children tables relationship, and I was trying to get each parent row with its latest child row details. My attempts to do that using a sub-query didn't work, and I could only made ...
HeyJude's user avatar
  • 457
0 votes
1 answer
31 views

Improving JOIN with sub-query

I capture Users who comment on the Articles of other Users, as INSERT IGNORE INTO AuthorCommentators (AuthorID,CommentatorID,Freq) SELECT AuthorID,CommentatorID,C FROM (SELECT b.UserID ...
Googlebot's user avatar
  • 4,531
-2 votes
1 answer
598 views

Having trouble with where subquery count

Assume all of the table and field names are correct. I've tried this a few different ways but this is the only that makes sense needing the join in both. This is the question: SQL query to get the ...
BFrank117's user avatar
0 votes
2 answers
90 views

How to UPDATE faster with GROUP BY?

I have a typical article and tag_map tables, CREATE TABLE `articles` ( `ID` int(11) unsigned NOT NULL, `Tags` tinyint(3) unsigned DEFAULT NULL, `Title` varchar(512) DEFAULT NULL, PRIMARY KEY (`...
Googlebot's user avatar
  • 4,531
0 votes
2 answers
73 views

Independent aggregation of related entities, while also sorting by related (in a single statement)

I have a model with books and authors, with a many-to-many relationship between them (because a book can have multiple authors, and an author can write multiple books) through a table which I've named ...
Inkling's user avatar
  • 101
7 votes
2 answers
10k views

Does Postgres optimize this JOIN with subquery?

In Postgres 12, I have a table purchase_orders and one for its items. I'm running a query that returns PO's for a given shop and a sum of items ordered on each PO: SELECT po.id, SUM(...
flavio's user avatar
  • 73
1 vote
1 answer
38 views

How to JOIN a table with itself while using a sub-query?

I JOIN a table to itself as SELECT t1.TagID AS TagID1 ,t2.TagID AS TagID2 ,COUNT(1) FROM TagMap AS t1 JOIN TagMap AS t2 ON t1.ArticleID = t2.ArticleID AND t1.TagID <> t2.TagID GROUP BY ...
Googlebot's user avatar
  • 4,531
3 votes
1 answer
20k views

ERROR: subquery must return only one column

I have two tables one is Category and other one is Product. Table Description are Category name description parent_id (self referencing key) (can be upto 3 levels) Product name description type ...
Chitrank Dixit's user avatar
0 votes
0 answers
69 views

I'm having trouble generating a list of downloadable items (data from three tables) with a column showing most recent download time for each

I am using the following query to generate a comprehensive download log with data from multiple tables (reduced to three for this example): SELECT wp_download_log.ID ,wp_download_log....
user2461674's user avatar
0 votes
2 answers
308 views

Inherit INNER JOIN fields in MySql SELECT QUERY

I want to know how I can join one field of an INNER JOIN table in a SELECT QUERY. Here's what i got so far: In this query my result would be NameA, NameB and idC, but i want to join tableA and tableC ...
Chris's user avatar
  • 15
0 votes
4 answers
102 views

How to visualize joins between inner queries to their respective outer queries?

I seem to always have trouble visualizing what the meaning is when an inner query is joined to it's outer query. Here's an example: SELECT NM.MovieId, NM.MovieTitle FROM NinjaMovies AS NM WHERE ...
J.D.'s user avatar
  • 39.5k
0 votes
1 answer
635 views

How to show multiple record if has top 1

Hi currently having difficulty to query the result sorry a newbie here. i am trying to find the result of these two tables. i want to get all the records on table 2 with an effective date < 2019-12-...
Nathan's user avatar
  • 29
1 vote
1 answer
30 views

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 ...
scott's user avatar
  • 113
8 votes
1 answer
4k views

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 ...
André Reichelt's user avatar
0 votes
1 answer
58 views

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 ...
user71346's user avatar
  • 101
0 votes
1 answer
199 views

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 ...
Ugy Astro's user avatar
  • 111
0 votes
1 answer
48 views

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, ...
Rhidoy's user avatar
  • 101
0 votes
1 answer
145 views

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 ...
ΣΚΟΤ's user avatar
  • 111
1 vote
1 answer
118 views

Why Output is wrong after doing the left join as subquery

I have TWO QUERY which work perfect, but when i join those two query as LEFT JOIN the output become wrong. So what is the problem.? Query 1: select Batsman.innings_no, bowler, sum(...
Rhidoy's user avatar
  • 101
0 votes
0 answers
45 views

Comparing count of 2 tables, is this the correct way?

I'm building a survey system where A client that has many users A user can have multiple surveys. I have a table users and a table survey_completions, I'm wondering if this is the correct (or best) ...
Miguel Stevens's user avatar
1 vote
3 answers
4k views

How to apply outer limit offset and filters in the subquery to avoid grouping over the complete table used in subquery in Postgresql

I have legacy tables similar to the following: employee ------------------------------------ | employee_id | name ------------------------------------ | 1 | David | 2 ...
nimeshkiranverma's user avatar
0 votes
1 answer
756 views

How to optimize UPDATE with a nested SELECT subquery?

I wrote a complicated UPDATE query, and it works, but it looks menacing. Here's what I'm trying to do: In each topic user 'Bob123' posted anonymously. When you post anonymously in a topic, you get ...
Thrash Tech's user avatar
0 votes
1 answer
45 views

Which query execution will be faster

In the following queries, which query execution will be faster. When I tried executing them in SQLWorkbench, each time query execution time is varying. Also, can you guys suggest some better tools ...
Venkatesh_CTA's user avatar
0 votes
1 answer
7k views

How to join 3 tables in MySQL

I’m looking at 3 tables here with: 1 called Users containing a UserID. UserID is linked by a foreign key to UserID in a table called Orders. Within Orders there’s a PassengerID linked by a foreign ...
Peel1234's user avatar
-2 votes
1 answer
59 views

Subquery and subselection for Count/Number doesnt work

for example, for company (3) and his partners, I need the number of events with payouts. But i get only the number for one partner, im my example i have i have 3 tables (t_company, t_partner, t_event,...
B.Irneos's user avatar
1 vote
2 answers
1k views

How to use GROUP BY in an efficient way without losing attributes? [closed]

I am working with PostgreSQL. My idea is to group players who appear more than 3 times in table-a. table-a = <player_id, year_world, c, d, e> With the first subquery I get player_id and the ...
Braian Coronel's user avatar
-1 votes
1 answer
4k views

Replace Subquery with JOIN - MYSQL

Can you please suggest how i can replace subquery in fetching select columns to improve the performance of query : SELECT sa.id AS patAppIdSA, sa.rte_id AS patRTEId, sa.case_type_id AS ...
Shilpa Garg's user avatar
1 vote
3 answers
288 views

MYSQL Update data based on top 10 records of each user

I have a table users and other table user_scores. In user_scores, I save daily score of every user based on a algorithm. Now I want to calculate AVG user_score by only considering latest 10 records of ...
Jatin Seth's user avatar
1 vote
1 answer
27 views

Join or Replace colum value based on query

I have this query: SELECT h.name, i.name, i.delay, i.delay_flex, i.status, i.templateid, i.params, i.description FROM items as i LEFT JOIN hosts as h ON i.hostid = h.hostid AND i.type = 11 AND i....
CorTheZ's user avatar
  • 25
0 votes
1 answer
855 views

unable to add limit to the subquery

its my first question, please bear me. I have following tables Item id name description itemPurchaseDetail id item_id(FK) branch_id(FK) purchaseRate date Stock id item_id(FK) branch_id(FK) ...
vicky's user avatar
  • 15
1 vote
3 answers
12k views

Joining two tables by the nearest match

General problem: I want to do a left join on two huge tables, but there is no matching key - I want to join the left table with the "nearest" row in the right table. In this example I want to join ...
tobixen's user avatar
  • 211
3 votes
1 answer
2k views

Reuse results from correlated subqueries in same query

I have 4 tables (I actually have lots more that I want to do this with...but this is where I am starting). distr_catalogs: has many distr_catalog_brands, distr_catalog_system_types ...
cal1801's user avatar
  • 33
1 vote
2 answers
156 views

Possible to rewrite this query as a join?

I'm fairly certain it's possible to rewrite this as a join query but I'm just not sure how to approach it: SELECT events.*, (SELECT MAX(updated_at) FROM events e WHERE e.user_id =...
Aydin Hassan's user avatar
3 votes
2 answers
2k views

Join is causing other column data to change?

I'll lead off with saying that I am relatively new to databases and SQL and I am trying to make an addition to a View in SQL Server that a previous co-worker created. I am trying to join the ...
Dev 404's user avatar
  • 133
2 votes
1 answer
13k views

Filtering subquery results with group by

I have a join that works but seems hacky because it orders the subquery and uses group by to filter everything but the top subquery result. Without doing so, the cartesian product of s and ...
AndrewE's user avatar
  • 23
0 votes
1 answer
336 views

Select one row from n number table; Join / Union table with looping

I have a list table. locations_list id | location | table ---------------------- 1 | Location 1 | location_1 2 | Location 2 | location_2 3 | Location 3 | location_3 location_1 ...
Abel Jojo's user avatar
  • 113