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Copy values from one column to another in the same table
...ble name and it's surrounded by grave accent (aka back-ticks `) as this is MySQL convention to escape keywords (and TABLE is a keyword in that case).
BEWARE, that this is pretty dangerous query which will wipe everything in column test in every row of your table replacing it by the number (regardle...
Using “like” wildcard in prepared statement
I am using prepared statements to execute mysql database queries. And I want to implement a search functionality based on a keyword of sorts.
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What is the email subject length limit?
...255 is probably the most common (and more efficient) data column length in MySQL / MariaDB. Bytes are most certainly still relevant. MySQL will use 1 byte to store the length if it is less than 256, or more otherwise. Take a look at how C++ implements std::string if you think string lengths aren'...
Oracle: If Table Exists
...pts for an Oracle database, and was hoping Oracle had something similar to MySQL's IF EXISTS construct.
15 Answers
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Rails 3 datatypes?
...t by using :limit option with :integer. I have tested it on Rails 3 and MySQL, they are still working, just as said in the blog, they are signed integer.
– RacsO
Dec 18 '13 at 3:23
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Should I choose ActivePerl or Strawberry Perl for Windows? [duplicate]
....15.
I think I dropped Strawberry Perl after trying to install DBI + DBD::mysql on Windows 7 (which is a no brainer in ActivePerl; just click on the ppms and choose install).
But maybe that's solved by now. And maybe one can choose the directory where Strawberry Perl gets installed (I couldn't).
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LR性能指标解释 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...：1.服务器Linux（包括CPU、Memory、Load、I O）。2.数据库：1.Mysql 2.Oracle（缓存命中、索引、...监控指标
性能测试通常需要监控的指标包括：
1.服务器Linux（包括CPU、Memory、Load、I/O）。
2.数据库：1.Mysql 2.Oracle（缓存命中、索引、...
SQL Add foreign key to existing column
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MySQL / SQL Server / Oracle / MS Access:
ALTER TABLE Orders
ADD FOREIGN KEY (P_Id)
REFERENCES Persons(P_Id)
To allow naming of a FOREIGN KEY constraint, and for defining a FOREIGN KEY constraint on multiple columns, use th...
Hibernate: hbm2ddl.auto=update in production?
...tabase schema.
The awesome thing is that I can take a totally blank slate mysql database on my laptop, fire up the app, and right away the schema is set up for me. It also makes it easy to test schema changes by applying these to a local-dev or staging db first.
The easiest way to get started wit...
Split value from one field to two
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Unfortunately MySQL does not feature a split string function. However you can create a user defined function for this, such as the one described in the following article:
MySQL Split String Function by Federico Cargnelutti
With that fu...