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Swapping column values in MySQL
I have a MySQL table with coordinates, the column names are X and Y. Now I want to swap the column values in this table, so that X becomes Y and Y becomes X. The most apparent solution would be renaming the columns, but I don't want to make structure changes since I don't necessarily have permission...
XAMPP - MySQL shutdown unexpectedly
When I open XAMPP and click start MySQL button and it gives me an error.
I had started it just before, but now it isn't working.
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Efficient SQL test query or validation query that will work across all (or most) databases
...it of research along with help from some of the answers here:
SELECT 1
H2
MySQL
Microsoft SQL Server (according to NimChimpsky)
PostgreSQL
SQLite
SELECT 1 FROM DUAL
Oracle
SELECT 1 FROM any_existing_table WHERE 1=0
or
SELECT 1 FROM INFORMATION_SCHEMA.SYSTEM_USERS
or
CALL NOW()
HSQLDB (tested ...
SQL command to display history of queries
I would like to display my executed sql command history in my MYSQL Query Browser. What is the sql statement for displaying history?
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CHECK constraint in MySQL is not working
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MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
T...
PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
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To answer your concerns:
MySQL >= 5.1.17 (or >= 5.1.21 for the PREPARE and EXECUTE statements) can use prepared statements in the query cache. So your version of MySQL+PHP can use prepared statements with the query cache. However, make careful ...
pip install mysql-python fails with EnvironmentError: mysql_config not found
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It seems mysql_config is missing on your system or the installer could not find it.
Be sure mysql_config is really installed.
For example on Debian/Ubuntu you must install the package:
sudo apt-get install libmysqlclient-dev
Maybe...
App Inventor 2 DynamicComponents 拓展：动态创建AI2组件对象 · App Inventor 2 中文网
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通过 JSON 字符串创建组件。请参阅Wiki，了解如何创建自己的模板。
从屏幕和组件列表中移除指定 ID 的组件。由于该组件已被删除，因此你可以再次使用该 ID...
PDOException “could not find driver”
I have just installed Debian Lenny with Apache, MySQL, and PHP and I am receiving a PDOException could not find driver .
3...
XMLHttpRequest cannot load file. Cross origin requests are only supported for HTTP
... wamp? I am running wamp and still receiving this message. Apache, php and mysql are all up-to-date
– user2883071
Dec 24 '14 at 18:52
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