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Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
...heck your database transaction isolation level in the mysql cli:
mysql> SELECT @@GLOBAL.tx_isolation, @@tx_isolation, @@session.tx_isolation;
+-----------------------+-----------------+------------------------+
| @@GLOBAL.tx_isolation | @@tx_isolation | @@session.tx_isolation |
+----------------...
Create unique constraint with null columns
...houtMenu row first and then link it to a menu if necessary. It also makes selecting all the favorites in one query very difficult: I'd have to do something weird like select all the menu links first, and then select all the Favorites whose IDs don't exist within the first query. I'm not sure if I ...
Haskell Type vs Data Constructor
...to consider the difference between a concrete type (examples include Int, [Char] and Maybe Bool) which is a type that can be assigned to a value in your program, and a type constructor function which you need to feed a type to be able to be assigned to a value. A value can never be of type "list", b...
What should every developer know about databases? [closed]
...fluence that choice;
The concept of coverage (why you shouldn't just write SELECT *);
The difference between a clustered and non-clustered index;
Why more/bigger indexes are not necessarily better;
Why you should try to avoid wrapping filter columns in functions.
Designers should also be aware of ...
Setting “checked” for a checkbox with jQuery
...
also $(selector).checked to check is checked
– eomeroff
May 2 '11 at 23:56
6
...
Add shadow to custom shape on Android
...;/shape>
</item>
</layer-list>
Then you should have a selector with diferent versions of the button, something like:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawabl...
OrderBy descending in Lambda expression?
... orderby person.Name descending, person.Age descending
select person.Name;
is equivalent to:
var query = people.OrderByDescending(person => person.Name)
.ThenByDescending(person => person.Age)
.Select(person => person.Name);
...
SQL Server - stop or break execution of a SQL script
...SERROR to actually stop the script. E.g.,
:on error exit
IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[SOMETABLE]') AND type in (N'U'))
RaisError ('This is not a Valid Instance Database', 15, 10)
GO
print 'Keep Working'
will output:
Msg 50000, Level 15, St...
How to install Hibernate Tools in Eclipse?
...bosstools/updates/stable/
Inside JBoss Web and Java EE Development folder, select Hibernate Tools
Click on Next
Once installed click on Window -> Show View -> Others. A new window pops up. Click on folder Hibernate and select Hibernate Configurations to setup a DB connection. It is possible ...
What is the best way to iterate over a dictionary?
...e wrong collection type in the first place), you should iterate dictionary.Select( (kvp, idx) => new {Index = idx, kvp.Key, kvp.Value}) instead and not use .ElementAt inside the loop.
– spender
Mar 2 '15 at 2:17
...