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How do I check if an index exists on a table field in MySQL?
...
Try:
SELECT * FROM information_schema.statistics
WHERE table_schema = [DATABASE NAME]
AND table_name = [TABLE NAME] AND column_name = [COLUMN NAME]
It will tell you if there is an index of any kind on a certain column wi...
Multiple Updates in MySQL
... another useful option is not yet mentioned:
UPDATE my_table m
JOIN (
SELECT 1 as id, 10 as _col1, 20 as _col2
UNION ALL
SELECT 2, 5, 10
UNION ALL
SELECT 3, 15, 30
) vals ON m.id = vals.id
SET col1 = _col1, col2 = _col2;
...
How can I select an element by name with jQuery?
...
You can use the jQuery attribute selector:
$('td[name ="tcol1"]') // matches exactly 'tcol1'
$('td[name^="tcol"]' ) // matches those that begin with 'tcol'
$('td[name$="tcol"]' ) // matches those that end with 'tcol'
$('td[name*="tcol"]' ) // matche...
Log all queries in mysql
...global general_log = 1;
SET global log_output = 'table';
View the log
select * from mysql.general_log
Disable Query logging on the database
SET global general_log = 0;
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how can I Update top 100 records in sql server
...derived table to define the desired sort order as below.
;WITH CTE AS
(
SELECT TOP 100 *
FROM T1
ORDER BY F2
)
UPDATE CTE SET F1='foo'
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f...
How to easily initialize a list of Tuples?
..." }, new Hold { Id = 2, Name = "You" } };
var anonymousProjections = holds.Select(x => new { SomeNewId = x.Id, SomeNewName = x.Name });
var namedTuples = holds.Select(x => (TupleId: x.Id, TupleName: x.Name));
Reuse the tuples later with grouping methods or use a method to construct the...
Limit file format when using ?
...te of <input type = "file"> can help to provide a filter in the file select dialog box of the OS. For example,
<!-- (IE 10+, Edge (EdgeHTML), Edge (Chromium), Chrome, Firefox 42+) -->
<input type="file" accept=".xls,.xlsx" />
should provide a way to filter out files other...
How to get a user's client IP address in ASP.NET?
...TE_ADDR")
Else
Dim ipArray As String() = sIPAddress.Split(New [Char]() {","c})
Return ipArray(0)
End If
End Function
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Simpler way to put PDB breakpoints in Python code?
...t you'll have to record your own (rather than copy/paste above) as special chars are involved (for escape etc).
– arcseldon
Feb 18 '19 at 6:54
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HTML5: number input type that takes only integers?
...f chrome. It does not allow letters to be typed, but it does allow special characters to be inserted.
– Malavos
Feb 21 '15 at 21:39
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