A core SQL statement, SELECT retrieves data from one or more tables or other sources of row set data such as views or table-valued functions.
1
vote
1answer
27 views
MySQL - how can I make a select statement get blocked?
Hello I am trying to intentionally make a SQL select statement get blocked by another simple SQL delete or update statement, for the purpose of learning. I prefer only InnoDB tables.
To prepare the ...
-1
votes
3answers
96 views
Add Contents in a Column and make them 0 [closed]
http://sqlfiddle.com/#!3/96f11/3
In the above fiddle, I need the required output in the Fiddle.
ie., The UserID column in Filtered Table and Main table are equal.
I need to get the Amt column data ...
1
vote
2answers
75 views
Getting SELECT to return a constant value even if zero rows match
Consider this select statement:
SELECT *,
1 AS query_id
FROM players
WHERE username='foobar';
It returns the column query_id with value 1 along with a player's other columns.
How would ...
0
votes
1answer
77 views
Error “column does not exist” in a SELECT with JOIN and GROUP BY querry
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 ...
0
votes
2answers
65 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`
+--------------+ ...
1
vote
2answers
28 views
Order by on an alphanumerical column
I have a column that has strings of the following type:
Miller 10
Allen 20
King 10
....
Jones 100
I try to sort the column based on the numerical part of the data.
I tried the following:
SELECT ...
1
vote
1answer
80 views
select count(*) in mysql 5.5 innodb— rewrite advice?
I need advice on how to rewrite a select count(*) query for innodb tables mysql 5.5. in new environment its very slow...
select count(*)
from mails3
join questions using (question_id)
where ...
0
votes
0answers
32 views
SQL SELECT when child table contains zero rows [migrated]
Let's say I have two tables:
Table A
employeeID (int)
employeeName (varchar)
employeeDOB (varchar)
Table B
employeeID (int)
holidaysUsed (int)
Table B is relational to Table A via employeeID. ...
-4
votes
2answers
120 views
Get Hierarchial Data in Self-Referencing Table (Parents , Childs) [closed]
In the following Fiddle,
sqlfiddle
I will pass a sno and I need all the parents of that sno in a table. And all the children of that sno in another table
Please refer to this question. Since ...
2
votes
2answers
52 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 ...
-1
votes
2answers
98 views
Select query having count and variable
I have a table like the one below.
I need to form a select query. I'm going to pass a RefID like
SELECT SNo FROM Register WHERE RefID = 1
And beside the SNo in the Statement, I need to have ...
1
vote
1answer
61 views
Insert from one row to another using cases
My original table was(being used since 2005):
CREATE TABLE `request` (
`msg` VARCHAR(150) NOT NULL,
`id` VARCHAR(20) NOT NULL,
`ctg` VARCHAR(10) NOT NULL DEFAULT 'misc',
`date` ...
0
votes
1answer
63 views
Optimization of a select statement
I'm using MySQL and have a table user_data like this:
user_id int(10) unsigned
reg_date int(10) unsigned
carrier char(1)
The reg_data is the unix timestamp of the ...
3
votes
1answer
36 views
PostgresSQL: Get single attribute of UDT in SELECT statement
I created a user-defined type in a PostgreSQL 9.2 database and am trying in the SELECT statement to get only an attribute of the UDT. However, I don't seem to get my code to work.
Creation of type ...
2
votes
1answer
107 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 ...
