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Swapping column values in MySQL
...rows affected (0.08 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM swaptest;
+------+------+
| X | Y |
+------+------+
| 1 | 2 |
| 3 | 4 |
| -5 | -8 |
| -13 | 27 |
+------+------+
4 rows in set (0.00 sec)
mysql>
Here is the swap being performed
m...
LINQ query on a DataTable
...w in myDataTable.AsEnumerable()
where myRow.Field<int>("RowNo") == 1
select myRow;
And as @Keith says, you'll need to add a reference to System.Data.DataSetExtensions
AsEnumerable() returns IEnumerable<DataRow>. If you need to convert IEnumerable<DataRow> to a DataTable, use the...
How do you display code snippets in MS Word preserving format and syntax highlighting?
...d install Notepad++ and do the following:
Paste your code in the window;
Select the programming language from the language menu;
Select the text to copy;
Right click and select Plugin commands -> Copy Text with Syntax Highlighting;
Paste it into MS Word and you are good to go!
Update 29/06/20...
How to check for Is not Null And Is not Empty string in SQL server?
... ('A'),
(''),
(' '),
(NULL);
SELECT *
FROM T
WHERE C <> ''
Returns just the single row A. I.e. The rows with NULL or an empty string or a string consisting entirely of spaces are all excluded by this query.
SQL Fiddle
...
android button selector
This is a button selector such that when normal it appears red, when pressed it appears grey.
6 Answers
...
MySQL复制的概述、安装、故障、技巧、工具 - 数据库(内核) - 清泛网 - 专注...
...表可以使用不同的键类型。比如主服务器用InnoDB，键用VARCHAR的话节省空间，从服务器使用MyISAM，键用CHAR提高速度，因为MyISAM有静态表一说。
主从服务器中的表可以使用不同的索引。主服务器主要用来应付写操作，所以除了主...
jQuery $(“#radioButton”).change(…) not firing during de-selection
...Andomar's solution worked but this makes more sense to me. Using the class selector prevents having to change the function if the form changes or has a dynamic number of fields. Yay for necro votes! (though now 2 years later jQuery recommends using prop() instead of attr(). api.jquery.com/prop)
...
MongoDB relationships: embed or reference?
...ill tied to text messages and Ruby 1.4 strings; in other words still ASCII chars only.
– John F. Miller
Sep 8 '17 at 18:52
|
show 4 more com...
fatal error: malformed or corrupted AST file - Xcode
...olved the issue for me. In Xcode, go to Window->Organizer->Projects, select your project, and press the "Delete..." button next to "Derived data".
If this doesn't work, you can try to do a Product->Clean (Cmd+Shift+k).
...
How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...