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Delete with Join in MySQL
...ect_id = posts.project_id AND projects.client_id = :client_id;
BTW, with mysql using joins is almost always a way faster than subqueries...
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How to change MySQL column definition?
I have a mySQL table called test:
3 Answers
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How do I list all cron jobs for all users?
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You would have to run this as root, but:
for user in $(cut -f1 -d: /etc/passwd); do crontab -u $user -l; done
will loop over each user name listing out their crontab. The crontabs are owned by the respective users so you won't be able to see another u...
How to select the last record of a table in SQL?
...s something like
Sql Server
SELECT TOP 1 * FROM Table ORDER BY ID DESC
MySql
SELECT * FROM Table ORDER BY ID DESC LIMIT 1
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mysql create user if not exists
I have a query to check mysql users list for create new user.
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Creation timestamp and last update timestamp with Hibernate and MySQL
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I would do this using a MySQL trigger so that even if the full entity is not saved or is modified by any external application or manual query, it'll still update these fields.
– Webnet
Jul 25 '13 at 12:09
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Unique constraint that allows empty values in MySQL
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Yes, you can do this. See the MySQL reference (version 5.5).
A UNIQUE index creates a constraint such that all values in the index must be distinct. An error occurs if you try to add a new row with a key value that matches an existing row. For all eng...
When and why are database joins expensive?
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MySQL, Oracle, SQL Server, Sybase, postgreSQL,etc. care not the order of joins. I've worked with DB2 and it also, to my knowledge, doesn't care what order you put them in. This is not helpful advice in the general case
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How to move columns in a MySQL table?
Currently I am having the following MySQL table: Employees (empID, empName, department);
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Read properties file outside JAR file
...am is main.jar and its main properties file is main.properties):
./ - the root of your program
|__ main.jar
|__ main.properties
With this architecture, you can modify any property in the main.properties file using any text editor before or while your main.jar is running (depending on the curren...