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How do you use script variables in psql?
...t myvariable value
... and can then be substituted, for example, as ...
SELECT * FROM :myvariable.table1;
... or ...
SELECT * FROM table1 WHERE :myvariable IS NULL;
edit: As of psql 9.1, variables can be expanded in quotes as in:
\set myvariable value
SELECT * FROM table1 WHERE column1 ...
Remove Identity from a column in a table
...USTERED INDEX IX_Original_Value ON Original (Value);
INSERT INTO Original
SELECT 'abcd'
UNION ALL
SELECT 'defg';
You can do the following:
--create new table with no IDENTITY
CREATE TABLE Original2
(
Id INT PRIMARY KEY
, Value NVARCHAR(300)
);
CREATE NONCLUSTERED INDEX IX_Original_Value2 ON O...
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...
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.
...
Sorting dropdown alphabetically in AngularJS
...
Angular has an orderBy filter that can be used like this:
<select ng-model="selected" ng-options="f.name for f in friends | orderBy:'name'"></select>
See this fiddle for an example.
It's worth noting that if track by is being used it needs to appear after the orderBy filt...
How to select rows from a DataFrame based on column values?
How to select rows from a DataFrame based on values in some column in Pandas?
10 Answers
...
ORDER BY the IN value list
... (introduced in PostgreSQL 8.2) VALUES (), ().
Syntax will be like this:
select c.*
from comments c
join (
values
(1,1),
(3,2),
(2,3),
(4,4)
) as x (id, ordering) on c.id = x.id
order by x.ordering
share...
Max or Default?
...d, you can get around this limitation by casting to a nullable within your select. My VB is a little rusty, but I think it'd go something like this:
Dim x = (From y In context.MyTable _
Where y.MyField = value _
Select CType(y.MyCounter, Integer?)).Max
Or in C#:
var x = (from y...
How to get the number of days of difference between two dates on mysql?
...lues are
used in the calculation
In your case, you'd use :
mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
| 3 |
+--------------...
this.setState isn't merging states as I would expect
...do recursive merge.
You can use the value of the current state this.state.selected to construct a new state and then call setState() on that:
var newSelected = _.extend({}, this.state.selected);
newSelected.name = 'Barfoo';
this.setState({ selected: newSelected });
I've used function _.extend() ...