Tagged Questions
3
votes
3answers
96 views
Are individual queries faster than joins?
Conceptual question: Are individual queries faster than joins, or: Should I try to squeeze every info I want on the client side into one SELECT statement or just use as many as seems convenient?
...
0
votes
2answers
31 views
Join on different types
In a database I have two tables:
The first has a field named taxonomy_id that is an integer
The latter has a field named ID that is a character varying
The two tables are related: if it exists a ...
2
votes
1answer
32 views
How can I include more query in one query?
These are my tables:
tbl_answers =>
aid
qid
answer
uid
dateposted
emailnotify
namedisplay
status
isbestanswer
tbl_questions =>
qid
question
...
0
votes
2answers
28 views
Query WHERE clause and JOIN
I'm having an issue using a WHERE clause and JOIN.
SELECT * FROM `CallDetailRecord`
WHERE `StartTime` >=1357102799000
AND `StartTime` <=1357880399000
JOIN `CallEvent` ON `EventID` = ...
-2
votes
3answers
78 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 ...
0
votes
1answer
58 views
Complicated join with where clause
I have four tables:
sales
sales_thumbs
sales_images
sales_sizes
sales table:
+--------------+---------------------+------+-----+---------+----------------+
| Field | Type | ...
0
votes
2answers
58 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 ...
0
votes
2answers
91 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`
+--------------+ ...
2
votes
2answers
58 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 ...
2
votes
2answers
57 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)
...
2
votes
1answer
119 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 ...
1
vote
1answer
73 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 ...
-1
votes
1answer
77 views
Want to show 3 tables in the same gridview and want to update/delete in parallel [closed]
Suppose I have 3 tables. But I want to show them it in same gridview and want to update and delete operations in parallel. How can I do that?
table 1: workshop
id contents demonstration ...
1
vote
1answer
97 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, ...
3
votes
1answer
73 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 ...
1
vote
1answer
167 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 ...
2
votes
2answers
85 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
----------
...
3
votes
1answer
152 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:
...
4
votes
3answers
174 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 ...
1
vote
0answers
133 views
Multi-Table Join to Single Destination
I am having a serious performance issue with join together four tables and placing the results (in a certain permutation) into one destination table. I am using MSSQL 2008 and good ole T-SQL.
To ...
2
votes
3answers
653 views
Alternative query to this (avoid DISTINCT)
Note: I work with MSSQL 2008, but I guess it's valid for many others DB engines
I have this table "Users":
UserID User CountryID
1 user 1 1
2 user 2 2
3 user 3 3
4 user ...
2
votes
1answer
293 views
Should I use left join to do my job in this scenario?
What I want to do is to find out the items which appeared more than once in this table:
mysql> desc tables;
+-----------------+---------------------+------+-----+---------+-------+
| Field ...
1
vote
1answer
126 views
Querying multiple tables
I am working on a query from our ticketing system, and I am having problems figuring out the best way to join these tables together.
I have the following tables/fields:
SR_service: stores ticket ...
0
votes
3answers
457 views
INNER JOIN making COUNT(*) slow
I have a very simple query:
SELECT COUNT(*)
FROM messages
INNER JOIN users ON messages.user_id = users.user_id
With the join it takes 1146 ms and without it takes 220 ms (220 ms still seems slow to ...
2
votes
1answer
294 views
Help with a complicated MySQL Query inserting data using select from 2 tables
I am stuck with a case and unable to get the desired result from my query..
I have to insert into a table some records based on multiple records from 2 different tables..
Tables: Target: ...
1
vote
1answer
288 views
Unable to add records to query in Access 2007
I've found this excellent resource that covers why a query might be read-only. I have a query that is not read only, yet I'm unable to add new records to it.
There are three tables. Let's call them ...
1
vote
1answer
454 views
Really slow DISTINCT ON query with multiple joins
Originally posted:
http://stackoverflow.com/questions/11173717/expensive-query-on-select-distinct-with-multiple-inner-join-in-postgres
The songs table has only about 4k rows, posts and stations have ...
1
vote
1answer
398 views
Combine column from multiple rows into one row in SQLITE
I have a sqlite-database with the schema
Articles
Id
Name
Tags
Id
Name
ArticlesTags
Id
ArticleId
TagId
I´m trying to query for Articles.Name and a LIST of tags. Basically what I would want ...
2
votes
1answer
112 views
Rewriting a query and eliminating subqueries
I have the following query :
SELECT ws_id, n50, num_singletons, num_segments_less_100, kmer, num_all_reads, number_bases_in_contigs,
num_bases_in_singletons
FROM stats_assembly WHERE ws_id IN (
...
3
votes
1answer
313 views
How to order query results by tag weight in IN('tag1', 'tag2', 'tag3')
Consider a simple query as
SELECT * FROM posts
JOIN tags USING(post_id)
JOIN tag_map USING(tag_id)
WHERE tags.tag IN('tag1', 'tag2', 'tag3')
tag_map is a many-to-many relationship between tables ...
1
vote
1answer
1k views
What joins are available in Informix 9.2?
I'm testing some queries with an old version of Informix (9.2.1) and can't seem to execute even the most basic queries containing RIGHT OUTER JOIN or FULL OUTER JOIN. Tried several variations (RIGHT ...
3
votes
3answers
310 views
SQL JOIN Syntax in MS SQL
I have been taught in my MSSQL classes, this is how to join two tables
select * from FirstTable A
JOIN SecondTable B
on A.ID= B.ID
Now in my professional life, I came across JOIN queries like ...
1
vote
2answers
687 views
LEFT JOIN conversion to INNER JOIN, can't change FROM clause
I have 2 tables:
BASE is master and is linked with CHILD via field ID: Left outer Join / 1:N relation.
These 2 tables contain historised data, defined by 2 date-fields: start_date and end_date.
...
6
votes
1answer
178 views
Table order in Join Query
if i say:
Table1 left join Table2
is it the same as saying
Table2 right join Table1
?
In other words, should i expect to get the same results from 2 identical queries where the only thing that is ...
0
votes
1answer
1k views
How can I select the latest record having one state where no later records exist with any other state?
I want to select the last record (by datetime) having a given state where no later records exist with any other state for each given "widget".
widget state timestamp
------ ----- ...
6
votes
3answers
1k views
Why is this Full Outer Join not working?
I've used Full Outer Joins before to get my desired results, but maybe I don't fully understand the concept because I am not able to accomplish what should be a simple join.
I have 2 tables (which ...
2
votes
4answers
3k views
Full Outer Join in MS Access
I have two staff lists:
List A:
StaffID Supervisor
====================
0001234 NULL
0001235 0001234
0001237 0001234
0001239 0001237
and
List B:
StaffID Supervisor
...
1
vote
1answer
62 views
How can this data be joined?
Definition:
table_A table_B
id,description id,description,id_table_A
Column id_table_A is a foreign key to the primary key of table_A and is not mandatory.
Sample data:
...
1
vote
1answer
219 views
Usefulness of Foreign Key WITHOUT reference option
Sorry, if this is naive question, but I searched a lot and did not get a vivid answers. Consider a simple InnoDB FOREIGN KEY without ON DELETE or ON UPDATE
I think this will avoid INSERT of a value ...
2
votes
2answers
143 views
Validation of availability for a new order
I have a management application of sales, stock and payment on a warehouse whole saler from a web interface. In particular, when a order is effectuated it must create a line corresponding to each ...
2
votes
3answers
230 views
Express union which is dependent on other results
I would like to make a union of two tables that are actually in a hierarchical constellation.
How would I write that in relational algebra? Say table A is the parent of B in a 1:n relationship.
...
5
votes
2answers
624 views
The order of INNER JOIN's
I would like to know if there are any rules about the order of INNER JOIN's in T-SQL 2000.
I had 62x the performance on my query when my INNER JOIN that act like a filter is placed at first instead ...
0
votes
1answer
1k views
Oracle SQL for left outer join to rownum = 1 of another query?
Background
I have a query joining many tables together, the chief of which is a workorder table.
I also have a table called WOStatusHistory, which stores every status for every workorder.
A diagram ...
2
votes
2answers
734 views
Update column by comparing date and string values together
I have problem in updating table.
I need to update table by comparing date and name with another table.
I have two tables:
table 1 : dim_sesid
name(varchar) role
...
7
votes
3answers
369 views
Oracle's left join and where clauses errors
CREATE TABLE "ATABLE1"
(
"COLUMN1" VARCHAR2(20 BYTE),
"COLUMN2" VARCHAR2(20 BYTE)
);
CREATE TABLE "ATABLE2"
(
"COLUMN1" VARCHAR2(20 BYTE),
"COLUMN2" VARCHAR2(20 BYTE)
);
...
9
votes
3answers
2k views
Should I use SQL JOIN or IN Clause?
I have a question about best approach. I am not sure which approach is best when data is considered variable in size.
Consider the following 3 TABLES:
EMPLOYEE
EMPLOYEE_ID, EMP_NAME
PROJECT
...
1
vote
1answer
227 views
Visually create a join using PHPMyAdmin
I recently started using SQL Server 2008 express and it has a really nice joins interface, whereby you can visually create a join. Is this possible on PHPMyAdmin?
2
votes
1answer
2k views
Using multiple PIVOTs JOINs and GROUP BYs for advanced report generation
I've developed a timesheet recording system, that allows users to record:
A Period of time (9:00 to 12:00)
What they did during that time (DutyActivity: 1 hour report writing, 2 hours training)
...
3
votes
2answers
258 views
How do I calculate working business minutes?
I'm working on business inteligence reports and one of my task is to create reports for time tracking.
I have to report on business minutes (10 hours per day) within business week (monday to ...
2
votes
1answer
433 views
SQL Return Count of Answers with 0's for Choices from another table
My question went dead after one unhelpful answer on SO here
I need this to be optimized because it will be called often. It is going into a stored procedure.
I am given @slide (tblILDSlide.id) and ...
