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MySQL: Set user variable from result of query
...need to move the variable assignment into the query:
SET @user := 123456;
SELECT @group := `group` FROM user WHERE user = @user;
SELECT * FROM user WHERE `group` = @group;
Test case:
CREATE TABLE user (`user` int, `group` int);
INSERT INTO user VALUES (123456, 5);
INSERT INTO user VALUES (111111...
Using column alias in WHERE clause of MySQL query produces an error
... though, by putting the expression directly into the WHERE x IN y clause:
SELECT `users`.`first_name`,`users`.`last_name`,`users`.`email`,SUBSTRING(`locations`.`raw`,-6,4) AS `guaranteed_postcode`
FROM `users` LEFT OUTER JOIN `locations`
ON `users`.`id` = `locations`.`user_id`
WHERE SUBSTRING(`loca...
How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
... as follows:
Click File → Data Modeler → Import → Data Dictionary.
Select a DB connection (add one if none).
Click Next.
Check one or more schema names.
Click Next.
Check one or more objects to import.
Click Next.
Click Finish.
The ERD is displayed.
Export the diagram as follows:
Click ...
How do I query between two dates using MySQL?
...ember 29 2010 and January 30 2010). Try reversing the order of the dates:
SELECT *
FROM `objects`
WHERE (date_field BETWEEN '2010-01-30 14:15:55' AND '2010-09-29 10:15:55')
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jQuery get value of select onChange
I was under the impression that I could get the value of a select input by doing this $(this).val(); and applying the onchange parameter to the select field.
...
Select N random elements from a List in C#
I need a quick algorithm to select 5 random elements from a generic list. For example, I'd like to get 5 random elements from a List<string> .
...
Finding duplicate rows in SQL Server
...abase of organizations, and there are many duplicate rows. I want to run a select statement to grab all of these and the amount of dupes, but also return the ids that are associated with each organization.
...
Getting only Month and Year from SQL DATE
...o 'discard' the Days, Hours, etc
- Leaving a year/month only date field
SELECT
DATEADD(MONTH, DATEDIFF(MONTH, 0, <dateField>), 0) AS [year_month_date_field]
FROM
<your_table>
This gets the number of whole months from a base date (0) and then adds them to that base date. Thus ...
How do I get list of all tables in a database using TSQL?
...
SQL Server 2000, 2005, 2008, 2012, 2014, 2016, 2017 or 2019:
SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE='BASE TABLE'
To show only tables from a particular database
SELECT TABLE_NAME
FROM <DATABASE_NAME>.INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'...
MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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