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SQL Server dynamic PIVOT query?
... @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX);
SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(c.category)
FROM temp c
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = 'SELECT date, ' + @cols + ' from
(...
What is this operator in MySQL?
...d <> both give UNKNOWN with NULL on either side of the expression.)
SELECT *
FROM table
WHERE YourColumn IS NOT NULL;
can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> NULL);
...
INSERT with SELECT
I have a query that inserts using a select:
8 Answers
8
...
XPath: select text node
... XML:
<node>Text1<subnode/>text2</node>
How do I select either the first or
the second text node via XPath?
Use:
/node/text()
This selects all text-node children of the top element (named "node") of the XML document.
/node/text()[1]
This selects the first text-nod...
How can I remove the gloss on a select element in Safari on Mac?
On Macs and iOS devices, in Safari, a <select> element with a background color generates a gloss over itself. This does not seem to happen in other operating systems.
...
Finding duplicate values in a SQL table
...
SELECT
name, email, COUNT(*)
FROM
users
GROUP BY
name, email
HAVING
COUNT(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY ...
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...
How to check if an option is selected?
...
UPDATE
A more direct jQuery method to the option selected would be:
var selected_option = $('#mySelectBox option:selected');
Answering the question .is(':selected') is what you are looking for:
$('#mySelectBox option').each(function() {
if($(this).is(':selected')) ....
Check if a Postgres JSON array contains a string
...
As of PostgreSQL 9.4, you can use the ? operator:
select info->>'name' from rabbits where (info->'food')::jsonb ? 'carrots';
You can even index the ? query on the "food" key if you switch to the jsonb type instead:
alter table rabbits alter info type jsonb using ...
PostgreSQL Crosstab Query
... - not fit for missing attributes
crosstab(text) with 1 input parameter:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inacti...