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How do I set the value property in AngularJS' ng-options?
...following forms:
For array data sources:
label for value in array
select as label for value in array
label group by group for value in array
select as label group by group for value in array track by trackexpr
For object data sources:
label for (key , value) in object
select as la...
Simple way to calculate median with MySQL
...
In MariaDB / MySQL:
SELECT AVG(dd.val) as median_val
FROM (
SELECT d.val, @rownum:=@rownum+1 as `row_number`, @total_rows:=@rownum
FROM data d, (SELECT @rownum:=0) r
WHERE d.val is NOT NULL
-- put some where clause here
ORDER BY d.val
) ...
Simplest way to do a recursive self-join?
...
WITH q AS
(
SELECT *
FROM mytable
WHERE ParentID IS NULL -- this condition defines the ultimate ancestors in your chain, change it as appropriate
UNION ALL
SELECT m.*
FROM mytable m
...
XML Schema minOccurs / maxOccurs default values
...ml>
<body>
<xsl:for-each select="country">
<xsl:value-of select="countryName"/><br/>
<xsl:value-of select="capital"/><br/>
<xsl:value-of select="nation...
SQL: How to properly check if a record exists
...
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...
Caveats of select/poll vs. epoll reactors in Twisted
...o based apps ) leads me to believe that ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
...
How to drop all tables in a SQL Server database?
...VARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS t...
UITableView Setting some cells as “unselectable”
How can I set the UITableView's cell property to be unselectable? I don't want to see that blue selection box when the user taps on the cell.
...
How to check if command line tools is installed
...ars in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is installed and if yes to find the version installed?
...
How do I check if a column is empty or null in MySQL?
...
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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