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How can I find out what FOREIGN KEY constraint references a table in SQL Server?
...
Here it is:
SELECT
OBJECT_NAME(f.parent_object_id) TableName,
COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM
sys.foreign_keys AS f
INNER JOIN
sys.foreign_key_columns AS fc
ON f.OBJECT_ID = fc.constra...
General guidelines to avoid memory leaks in C++ [closed]
...tion will have a buffer "on the stack of the class" for small strings (~15 chars), and will use a pointer to a memory in the heap for larger strings... But from the outside, std::string is still a value type that you declare (usually) on the stack and you use as you would use an integer (as opposed ...
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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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...
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:
...
How do I create a category in Xcode 6 or higher?
...ey just moved it without telling anyone.
Click File -> New -> File
Select Objective-C file under Sources in iOS or Mac OS respectively and Click Next
Now under File Type: choose either Category, Protocol, or Extension
PS. Under File Name: whatever you type here will be either the Category,...
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...
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
...
Getting attribute using XPath
...e), for
the first element?
Use:
/*/book[1]/title/@lang
This means:
Select the lang attribute of the title element that is a child of the first book child of the top element of the XML document.
To get just the string value of this attribute use the standard XPath function string():
string(...
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...