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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...
How to insert a line break in a SQL Server VARCHAR/NVARCHAR string
...NVARCHAR(100)
SET @text = 'This is line 1.' + CHAR(13) + 'This is line 2.'
SELECT @text
This prints out the following:
This is line 1.
This is line 2.
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Android ViewPager with bottom dots
...droid:layout_height="wrap_content"
app:tabBackground="@drawable/tab_selector"
app:tabGravity="center"
app:tabIndicatorHeight="0dp"/>
</RelativeLayout>
Hook up your UI elements inactivity or fragment as follows:
Java Code:
mImageViewPager = (ViewPager) findViewById(R.id...
jQuery - Detecting if a file has been selected in the file input [duplicate]
...lt;/script>
You may want to add IDs to your input and span so you can select based on those to be specific to the elements you are concerned with and not other file inputs or spans in the DOM.
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Selecting element by data attribute
Is there an easy and straight-forward method to select elements based on their data attribute? For example, select all anchors that has data attribute named customerID which has value of 22 .
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Mysql error 1452 - Cannot add or update a child row: a foreign key constraint fails
... have to get rid of those first.
Here's a query that can find those IDs:
SELECT DISTINCT sourcecode_id FROM
sourcecodes_tags tags LEFT JOIN sourcecodes sc ON tags.sourcecode_id=sc.id
WHERE sc.id IS NULL;
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SQL JOIN vs IN performance?
...king, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
, unless b.col is unique.
However, this is the syno...
How to make certain text not selectable with CSS [duplicate]
...r my page has some centered text, but I do not want the user to be able to select it. Is there a way to do this with CSS?
2...
IntelliJ IDEA way of editing multiple lines
...ossibility to edit multiple lines.
Use:
Alt + Shift + Mouse click
for selection. More about this new improvement in IntelliJ blogpost here. Very useful feature.
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SQL to determine minimum sequential days of access?
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The answer is obviously:
SELECT DISTINCT UserId
FROM UserHistory uh1
WHERE (
SELECT COUNT(*)
FROM UserHistory uh2
WHERE uh2.CreationDate
BETWEEN uh1.CreationDate AND DATEADD(d, @days, uh1.CreationDate)
) = @days O...