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How to check if a column exists in a SQL Server table?
...
SQL Server 2005 onwards:
IF EXISTS(SELECT 1 FROM sys.columns
WHERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tabl...
How do I list all the columns in a table?
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For Oracle (PL/SQL)
SELECT column_name
FROM user_tab_cols
WHERE table_name = 'myTableName'
For MySQL
SHOW COLUMNS FROM table_name
share
|
i...
How to style the with only CSS?
How can I style <option> s of a <select> element with cross-browser compatibility? I know many JavaScript ways which customize the dropdown to convert into <li> , which I'm not asking about.
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MySQL Data - Best way to implement paging?
...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).
With two arguments, the first argument specifies the offset of the first ro...
SQL Query Where Field DOES NOT Contain $x
...t is meant to be used in subqueries or with predefined lists:
-- subquery
SELECT a FROM x WHERE x.b NOT IN (SELECT b FROM y);
-- predefined list
SELECT a FROM x WHERE x.b NOT IN (1, 2, 3, 6);
If you are searching a string, go for the LIKE operator (but this will be slow):
-- Finds all rows where...
Convert PEM to PPK file format
...rvers. This function will allow the user to create multiple custom keys by selecting the "My Account/Key Management" option. Once the key has been created the user will be required to select the desired SSH Key during the “Create Server” process for Linux.
Create and Use SSH Keys
Create keys
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Why do we always prefer using parameters in SQL statements?
I am very new to working with databases. Now I can write SELECT , UPDATE , DELETE , and INSERT commands. But I have seen many forums where we prefer to write:
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phpunit mock method multiple calls with different arguments
... ->with($this->logicalOr(
$this->equalTo('select * from roles'),
$this->equalTo('select * from users')
))
->will($this->returnCallback(array($this, 'myCallback')));
var_dump($mock->Query("select * from us...
convert a list of objects from one type to another using lambda expression
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Try the following
var targetList = origList
.Select(x => new TargetType() { SomeValue = x.SomeValue })
.ToList();
This is using a combination of Lambdas and LINQ to achieve the solution. The Select function is a projection style method which will apply the passe...
Search text in fields in every table of a MySQL database
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If you have phpMyAdmin installed use its 'Search' feature.
Select your DB
Be sure you do have a DB selected (i.e. not a table, otherwise you'll get a completely different search dialog)
Click 'Search' tab
Choose the search term you want
Choose the tables to search
I have used this ...