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How do I drop a foreign key constraint only if it exists in sql server?
...target a foreign key constraint on a specific table, use this:
IF EXISTS (SELECT *
FROM sys.foreign_keys
WHERE object_id = OBJECT_ID(N'dbo.FK_TableName_TableName2')
AND parent_object_id = OBJECT_ID(N'dbo.TableName')
)
ALTER TABLE [dbo.TableName] DROP CONSTRAINT [FK_TableName_TableName2]...
Convert List into Comma-Separated String
...s before you Aggragate to string. So you can do something like this: list.Select(x => string.Format("{0}:{1}", x.Key, x.Value)).Aggregate((a, x) => a+ ", " + x);
– bets
Jul 20 '17 at 8:14
...
PostgreSQL Autoincrement
...RT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter SERIAL onto an existing column.
sha...
When to use single quotes, double quotes, and backticks in MySQL
...ng query will produce different results (or errors) depending on SQL mode:
SELECT "column" FROM table WHERE foo = "bar"
ANSI_QUOTES disabled
The query will select the string literal "column" where column foo is equal to string "bar"
ANSI_QUOTES enabled
The query will select the column column where ...
Is it possible to for SQL Output clause to return a column not being inserted?
...d.ReportOptionId
INTO @PracticeReportOption (PracticeId, ReportOptionId)
SELECT field1, field2
FROM @ReportOption
with
MERGE INTO ReportOption USING @ReportOption AS temp ON 1 = 0
WHEN NOT MATCHED THEN
INSERT (field1, field2)
VALUES (temp.Field1, temp.Field2)
OUTPUT temp.Practice...
Which SQL query is faster? Filter on Join criteria or Where clause?
...INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = a.ID
AND a.ID = 1
LEFT JOIN
TableB b
ON x.TableBID = b.ID
or this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x...
The name 'InitializeComponent' does not exist in the current context
If I create a new project in Visual Studio 2010 SP1 and select "WPF Application" and tries to build the generated application, I get the error
...
Export a stash to another computer
... After reading this answer one thing I was wondering was how to select a particular stash from all my stashes. The answer to that is here: stackoverflow.com/a/1910142/1148702 . In this case I ended up doing: git stash show "stash@{0}" -p > patch instead of the OP's second shell command...
Simple way to copy or clone a DataRow?
...lone();
// Note: .Copy(), by contrast, would clone the data rows also.
// Select the data row to clone, e.g. the 2nd one:
var row = table.Rows[1];
// Import the data row of interest into the aux. table.
// This creates a *shallow clone* of it.
// Note: If you'll be *reusing* the aux. table for sin...
Get the new record primary key ID from MySQL insert query?
...
Eg:
INSERT INTO table_name (col1, col2,...) VALUES ('val1', 'val2'...);
SELECT LAST_INSERT_ID();
This will get you back the PRIMARY KEY value of the last row that you inserted:
The ID that was generated is maintained in the server on a per-connection basis. This means that the value returne...