大约有 40,000 项符合查询结果（耗时：0.0641秒） [XML]
Linq to SQL how to do “where [column] in (list of values)”
...CodeData>()
where codeIDs.Contains(codeData.CodeId)
select codeData;
But you might as well do that in dot notation:
var foo = channel.AsQueryable<CodeData>()
.Where(codeData => codeIDs.Contains(codeData.CodeId));
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How to get CSS to select ID that begins with a string (not in Javascript)?
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The specificity of this type of selector is very low
– nuander
Sep 3 '15 at 21:24
3
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Selecting data frame rows based on partial string match in a column
I want to select rows from a data frame based on partial match of a string in a column, e.g. column 'x' contains the string "hsa". Using sqldf - if it had a like syntax - I would do something like:
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How can I select every other line with multiple cursors in Sublime Text?
In Sublime Text 2, is it possible to instantly select every other (or odd/even) line and place multiple cursors on those lines?
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How to create a self-signed certificate for a domain name for development?
...g the IIS Manager
Launch the IIS Manager
At the server level, under IIS, select Server Certificates
On the right hand side under Actions select Create Self-Signed Certificate
Where it says "Specify a friendly name for the certificate" type in an appropriate name for reference.
Examples: www.dom...
SQL: How to properly check if a record exists
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It's better to use either of the following:
-- Method 1.
SELECT 1
FROM table_name
WHERE unique_key = value;
-- Method 2.
SELECT COUNT(1)
FROM table_name
WHERE unique_key = value;
The first alternative should give you no result or one result, the second count should be zero or on...
How do I check if a column is empty or null in MySQL?
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This will select all rows where some_col is NULL or '' (empty string)
SELECT * FROM table WHERE some_col IS NULL OR some_col = '';
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Most efficient T-SQL way to pad a varchar on the left to a certain length?
...cely. It will also perform the conversion for you:
declare @n as int = 2
select FORMAT(@n, 'd10') as padWithZeros
Update:
I wanted to test the actual efficiency of the FORMAT function myself. I was quite surprised to find the efficiency was not very good compared to the original answer from Al...
MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
13
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Why shouldn't I use mysql_* functions in PHP?
... 5.5 and above)
$link = mysql_connect('localhost', 'user', 'pass');
mysql_select_db('testdb', $link);
mysql_set_charset('UTF-8', $link);
With PDO: All you need to do is create a new PDO object. The constructor accepts parameters for specifying the database source PDO's constructor mostly takes fo...