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Multiple Indexes vs Multi-Column Indexes
I've just been adding an Index to a table in SQL Server 2005 and it got me thinking. What is the difference between creating 1 index and defining multiple columns over having 1 index per column you want to index.
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How can I create a copy of an Oracle table without copying the data?
... The command in my answer doesn't create the new table; it returns the SQL you would use to recreate the original table. You modify it as desired then run it. So the name of the new table is whatever you choose to specify.
– Dave Costa
Jul 18 '13 at 15:50...
How Pony (ORM) does its tricks?
Pony ORM does the nice trick of converting a generator expression into SQL. Example:
1 Answer
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SET NAMES utf8 in MySQL?
I often see something similar to this below in PHP scripts using MySQL
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怎么往SetTimer的回调函数传递参数 - C/C++ - 清泛网 - 专注C/C++及内核技术
...hMessage的循环，由于还是原来的线程，所以它GetMessage将还包括WM_TIMER，另外还有消息框自己的一些关于界面的消息，比如WM_PAINT，消息框 的出现只是在系统中又注册了一些需要的消息，就是消息框的关于界面事件的消息。WM_TIMER...
Multi-statement Table Valued Function vs Inline Table Valued Function
...lued function (MSTVF) even if they both simply execute a SELECT statement. SQL Server will treat an ITVF somewhat like a VIEW in that it will calculate an execution plan using the latest statistics on the tables in question. A MSTVF is equivalent to stuffing the entire contents of your SELECT statem...
How do you copy a record in a SQL table but swap out the unique id of the new row?
... have to specify. It's better than the other way around anyway. :-)
I use SQL Server. You may want to use "CREATE TABLE" and "UPDATE TABLE" at row 1 and 2.
Hmm, I saw that I did not really give the answer that he wanted. He wanted to copy the id to another column also. But this solution is nice for...
How do I add more members to my ENUM-type column in MySQL?
The MySQL reference manual does not provide a clearcut example on how to do this.
7 Answers
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Should MySQL have its timezone set to UTC?
...ill choose for his/her server and how he/she will store date and time.
MySQL Timezone Cheatsheet
Notes:
Changing the timezone will not change the stored datetime or
timestamp, but it will select a different datetime from
timestamp columns
Warning! UTC has leap seconds, these look like '2012-06...
How do I check if a Sql server string is null or empty
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In SQL Server 2012 you have IIF, e.g you can use it like
SELECT IIF(field IS NULL, 1, 0) AS IsNull
The same way you can check if field is empty.
sha...