An SQL join clause combines records from two or more tables or views.

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Missing values in INNER JOIN MS-Access?

When I run the following query in MS-Access: SELECT a1.ConStateNumber, a2.ConStateNumber FROM qryW2_yr_sum_slash_qryW2_q4_sum_result a1 INNER JOIN qryW2_q3_sum a2 ON a1.ConStateNumber = ...
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3answers
159 views

Left Join not giving desired result

I have two Datasets FEES PAYMENTS CrsCode InstNo FEE Regno CRSCODE Instno Payment CA1 -2 100 R1 CA1 -2 100 CA1 -1 200 ...
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1answer
257 views

How to add additional tables/fields into a query with multiple inner joins?

Given this query (many thanks to RolandoMySQLDBA from question Select records that do not have associations outside a certain list), how do I add other fields from other tables into my result? SELECT ...
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1answer
343 views

How to get rows where count() is null?

This is my SQL request : SELECT COUNT( b0_.id ) AS sclr0, d1_.codeLieu AS codeLieu1, d1_.nomLieu AS nomLieu2, d1_.lngLieu AS lngLieu3, d1_.latLieu AS latLieu4, m2_.libelleMention AS ...
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2answers
181 views

Slow query joining on subqueries with max

I'm creating a report based on user input (i.e. a search tool) that grabs data from eight tables and will output them to the screen. Here are the create table statements. I'm very aware of how badly ...
2
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1answer
800 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 ...
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1answer
444 views

Get data from two tables with recursive relationships

I have a MySQL 5.1 DB, being used behind a PHP application to track permissions and other items that need to be issued to staff that hold various positions within an org. To track what privileges a ...
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2answers
90 views

Database search with multi joins

I have a MySQL database and I want to perform a little bigger search. I have about 10k records in one of the tables and It's expected to grow, but slowly. The biggest problem is that to perform the ...
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1answer
968 views

update statement with self join

I needed to copy information from one row of a table to another. I noticed I could do the following: update address set col1 = a2.col1, col2 = a2.col2, .....etc from address a1, address a2 where ...
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1answer
2k views

Error “column does not exist” in a SELECT with JOIN and GROUP BY query

I'm using PostgreSQL 9.1 with a Ruby on Rails application. I'm trying to list the last version of each "charge" (in my history table : hist_version_charges) belonging to the same project id ...
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1answer
44 views

Getting the name of the column that was used in a join?

This may be a bit of a weird question: Our project's datamodel has multiple tables with multiple columns any one of which can be used to join with one settingtable. The question here is how to get ...
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35 views

parenthetic grouping of join clauses

What is the difference between these joins? a left join b left join c (a left join b) left join c a left join (b left join c) Does the grouping only affect the order of the joins? Will the query ...
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607 views

How can I join one to one to (many to one) without using group_concat

I have a table structure as follows: -- -- Table structure for table `emails` -- CREATE TABLE IF NOT EXISTS `emails` ( `ID` int(5) NOT NULL AUTO_INCREMENT, `email` varchar(255) COLLATE ...
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2answers
4k views

MySQL: Join one Row in a table with two Rows in other table

In my MYSQL Database COMPANY. I have two tables, like below in my diagram (arrow shows relations): `users` `user_login` +--------------+ ...
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1answer
851 views

Immediate refresh materialized views (MQT) with OUTER JOIN under DB2

DB2 accepts a materialized view based on an "OUTER JOIN" query, as long it doesn't refresh automatically (REFRESH IMMEDIATE). I cannot find a simple solution to get round this problem. Perhaps with ...
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1answer
106 views

Why is there such a huge performance difference in these two join statements?

I have a query which i first wrote as (query has been simplified a bit) : select ROW_NUMBER() OVER (ORDER BY c.CategoryTypeID), c.name, count(p.id) from category c inner join product p on p.indID = ...
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2answers
4k views

How to JOIN two table to get missing rows in the second table

In a simple voting system as CREATE TABLE elections ( election_id int(11) NOT NULL AUTO_INCREMENT, title varchar(255), CREATE TABLE votes ( election_id int(11), user_id int(11), FOREIGN KEYs for ...
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1answer
2k views

Oracle: Non key-preserved table should be

I'm getting "ORA-01779: cannot modify a column which maps to a non key-preserved table" when I try to update a join. I've searched around the site and found a lot of advice on what key-preserved ...
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2answers
224 views

Expand sparse table with self outer join on distinct values

I have this: g1 | g2 | x ---------+-----------+----- New York | Monday | 210 New York | Tuesday | 258 Chicago | Monday | 30 Chicago | Wednesday | 25 LA | Thursday | 40 ...
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2answers
651 views

Postgres RIGHT JOIN with custom array

I'm using Postgres 9.1 and want to get a result with some blanks where there is no data. My query looks like the following: SELECT institution_id FROM ... WHERE institution_id IN (1, 3, 4, 5, 7, 9) ...
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1answer
81 views

Speed efficient query for membership first joined, latest category from membership table (min, max)

I have the following table representing membership information: CREATE TABLE IF NOT EXISTS `membership` ( `id` int(11) NOT NULL AUTO_INCREMENT, `organisation_id` int(11) NOT NULL, ...
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1answer
157 views

How to write this self join based on three columns

Hello there I have a following table ------------------------------------------ | id | language | parentid | no_daughter | ------------------------------------------ | 1 | 1 | 0 | ...
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1answer
277 views

join the two tables which possess one to many relationship

In drupal,the content type table and my own table is used to do some operations. Im having two tables namely Table1:'content_field_mem_id' & Table2:'Ex' description of ...
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1answer
783 views

Selecting minimum value using a subquery

I need to write a query to grab the lowest price from each merchant and output the price link (p_link) and some other information such as merchant name + rating. We have a table for prices ...
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1answer
408 views

oracle huge hash_area_size

I am wondering what is the maximum setting for hash_area_size parameter? I'm trying to perform a huge join which ends up allocating 10Gb of temp space and completes in an hour. 10Gb is not that much ...
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1answer
117 views

Join Calender Table

I have a Datatable and a Calendartable. I do a join on this tables to get sequential dates if there is no data for this day. My problem now is that there a several id's and i need a count for each ...
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1answer
149 views

Mysql Join with filters

I have two tables: MAINCOLOR and SUBCOLOR with the data as: MAINCOLOR : MAINID COLOR 1 RED 2 BLUE 3 GREEN SUBCOLOR: SUBID MAINID SUBCOLOR STATUS 1 1 PINK 0 2 1 ...
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3answers
376 views

Complex query with multiple normalized fields

We have a fairly simple table structure, but with a LOT of fields per table (talking 40+). This data is initially produced in plain-text, user-readable tables, but then it is translated into ...
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2answers
362 views

How to get non repeat results

I've two tables default_tb_persona and default_tb_envio, this are the DDL for those tables: CREATE TABLE `default_tb_envio` ( `codigo` varchar(7) NOT NULL, `fecha` date NOT NULL, `id_modalidad` ...
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1answer
459 views

How and what is the most efficient way to join two tables, retaining a particular field from both?

I have two tables, with the following columns: Table 1 ID Component Data1 Data2 Table 2 ID Component Data3 Data4 If I have rows in these tables, with items Component1, Component2, Component3, ...
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3answers
3k views

Is it better to seperate a big query into multiple smaller queries?

There are situations which require to have really big query joining several tables together with sub select statements in them to produce the desired results. My question is, should we consider using ...
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1answer
744 views

How does mysql deal with queries that touches myisam and innodb tables?

In our mysql database, we use both myisam and innodb tables, though there are more myisam tables. QUESTIONS If a query involves both myisam and innodb tables, will the query use table lock or row ...
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2answers
639 views

Identify NON-ANSI joins in SQL Server 2008 R2 on a Database that's in 2000 (80) compatibility mode

We have a very old database running on SQL Server 2008 R2. The database is running in 2000 (80) compatibility mode and has oodles of NON-ANSI joins in stored procedures, views and functions. We need ...
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1answer
986 views

Select multiple columns in subquery

I am having trouble selecting all cloumns in a sub query and can't seem to get no where with joining for replacement. http://sqlfiddle.com/#!2/2481e/1 The link is to the schema with my current ...
4
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1answer
189 views

Is there a standard way to replace codes with values from a lookup table for reporting or analytics?

Suppose I have a "main" table that was probably heavily normalized and consists largely of columns that merely contain codes that are lookups into other tables (they are probably foreign keys but feel ...
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1answer
2k views

Retrieving data from inner join using LIMIT and OFFSET

These are my two tables: table1 qid[PK] |gid[PK] |abcd | xyz | date ---------------+---------+---------+------+------------ 00001 | qwe | 54 | a | 1994-11-29 00002 ...
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1answer
3k views

Subqueries run very fast individually, but when joined are very slow

ypercube solved the problem. Subqueries were totally unnecessary, and the whole thing works with plain joins. It is still strange that MySQL's optimizer could not make use of my original query, ...
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1answer
521 views

Group By on column from joined table

its about the following query. EXPLAIN SELECT phrase, infinitiv FROM `dict_verbs_all` `t` INNER JOIN `dict_verbs_all_language` `verbsGerman_c` ON (`t`.`id`=`verbsGerman_c`.`verb_id`) INNER JOIN ...
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2answers
305 views

Tuning query to remove joins for reporting

This is the query I was sent. There is currently no data in the system as I was converting this query from teradata to SQL server. SELECT user_id FROM user_table LEFT OUTER JOIN ( SELECT user_id , ...
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2answers
162 views

Counting results for cross join

How I can get count results with cross join? Example cross join: SELECT t1.firstname, t2.lastname FROM table1 t1 CROSS JOIN table1 t2
4
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1answer
377 views

NEWID() In Joined Virtual Table Causes Unintended Cross Apply Behavior

My actual work query was an inner join, but this simple example with cross join seems to nearly always reproduce the problem. SELECT * FROM ( SELECT 1 UNION ALL SELECT 2 ) AA ( A ) CROSS JOIN ...
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2answers
109 views

Joining 4 tables and 2 counts

I have four tables. UserMaster ---------- UserKey - PK UserName UserID - UNIQUE UserLogTransaction ------------------ UserID - FK:UserMaster.UserID LoginTime LogoutTime CallCenter ---------- ...
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2answers
530 views

Slow query with straight_join for small result

I have a performance-problem with a query in my application and I don’t understand the behavior of mysql. The query consists of different joins, especially the join to the mentioncache-table. If the ...
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3answers
2k views

Join tables on a partial string match

input: I have a table containing (any number of) user-supplied strings: ╔═══════╗ ║ Value ║ ╠═══════╣ ║ To ║ ║ An ║ ╚═══════╝ And a table of user details: ╔════════╦══════════╗ ║ UserID ║ ...
2
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1answer
89 views

JOIN 2 tables, and query data from them 3 times

Basically I have 2 tables: post_meta and posts. post_meta has a post_id, key and value: post_id key value 6343 make Chevy 6343 model Volt 6794 make Chevy 6794 model ...
3
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1answer
349 views

Complex SQL Query

I'm trying to formulate a single query to return a nice list of a host's interfaces and the interfaces attributes from the Cacti MySQL DB. Here are the tables I am referencing: host_snmp_cache: ...
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1answer
482 views

Update ranking on table

I have two tables: mysql> desc rank ; +----------------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | ...
2
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1answer
481 views

inner join on PK with extra criteria slow despite indices?

Given the two tables below I am struggling to understand: why is the third query slow even though first two queries are fast what exactly is EXPLAIN saying can I do anything to significantly speed ...
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2answers
586 views

SQL ANSI JOIN precedence

I have a query that looks like this: SELECT * FROM TBLA A LEFT JOIN TBLB B ON A.Col1 = B.Col2 RIGHT JOIN TBLC C ON B.Col3 = C.Col4 JOIN TBLD D ON C.Col5 = D.Col6 In which order ...
5
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3answers
636 views

Many-to-Too-Many Relationship

I'm working on a book database. And among others, I have the following two tables (a bit simplified for the question): tblBook: ID, Title tblPerson: ID, Name Note that the tblPerson table contains ...