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Default implementation for Object.GetHashCode()
...sually more interested in whether a string containing the same sequence of characters has already been added. That's why string overrides GetHashCode. On the other hand, suppose you want to keep a count of how many times various controls process Paint events. You could use a Dictionary<Object,...
Replacing NULL with 0 in a SQL server query
...u want to replace a possibly null column with something else, use IsNull.
SELECT ISNULL(myColumn, 0 ) FROM myTable
This will put a 0 in myColumn if it is null in the first place.
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MySQL: Transactions vs Locking Tables
...ransactions vs locking tables to ensure database integrity and make sure a SELECT and UPDATE remain in sync and no other connection interferes with it. I need to:
...
What is the point of the diamond operator () in Java 7?
...de by saving repeated type arguments. In practice, it's just two confusing chars more giving you nothing. Why?
No sane programmer uses raw types in new code. So the compiler could simply assume that by writing no type arguments you want it to infer them.
The diamond operator provides no type infor...
C#/Linq: Apply a mapping function to each element in an IEnumerable?
...
You can just use the Select() extension method:
IEnumerable<int> integers = new List<int>() { 1, 2, 3, 4, 5 };
IEnumerable<string> strings = integers.Select(i => i.ToString());
Or in LINQ syntax:
IEnumerable<int> in...
Android Studio Editor Font Sizing
...
In MacBook Android Studio ->
Select Preferences... ->
Click on Save As.. ->Give any name -> OK -> then select Scheme -> and you given name every option Editable
s...
UTF-8 without BOM
... solution to your problem:
If you want to save a file with other encodings select save as and extend the save button in file dialog and select "Save with encoding". Or if you you want to get rid of this setting permanently just open File menu and select "Advanced save options" and there you should s...
How to remove a column from an existing table?
...lete a column from an unexisting table ;-)
BEGIN TRANSACTION
IF exists (SELECT * FROM sys.columns c
INNER JOIN sys.objects t ON (c.[object_id] = t.[object_id])
WHERE t.[object_id] = OBJECT_ID(N'[dbo].[MyTable]')
AND c.[name] = 'ColumnName')
BEGIN TRY
ALTER TABLE [dbo].[MyTable] DRO...
SET NOCOUNT ON usage
...OUNT is ON. Depends on client lib implementation in cases when query holds SELECT statements or RPC calls that do select, it may require to disable counting... WHEN disabled, rows are still counted for select statement, but flag DONE_COUNT is set to false. Always read what your client lib suggests s...
Images can't contain alpha channels or transparencies
...rt to PNG without alpha in Preview. Simply open your image, choose export, select PNG, uncheck Alpha, and click Save. Preview also support batch export if you open all your images at once.
– Russell Ladd
Jan 7 '15 at 6:23
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