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How to get a list of column names on Sqlite3 database?
...
but you can't select from that table. It's just plain annoying. I'm trying something like this... but it don't work create temporary table TmpCols (cid integer, name text, type text, nn bit, dflt_value, pk bit); .mode insert TmpCols .out...
Swapping column values in MySQL
...rows affected (0.08 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM swaptest;
+------+------+
| X | Y |
+------+------+
| 1 | 2 |
| 3 | 4 |
| -5 | -8 |
| -13 | 27 |
+------+------+
4 rows in set (0.00 sec)
mysql>
Here is the swap being performed
m...
Move capture in lambda
...t;type_traits>
#include <functional>
namespace detail
{
enum selection_enabler { enabled };
}
#define ENABLE_IF(...) std::enable_if_t<(__VA_ARGS__), ::detail::selection_enabler> \
= ::detail::enabled
// This allows forwarding an object using the copy c...
Can overridden methods differ in return type?
... class Alpha {
Alpha doStuff(char c) {
return new Alpha();
}
}
class Beta extends Alpha {
Beta doStuff(char c) { // legal override in Java 1.5
return new Beta...
SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
...
select COUNT_BIG(*) FROM Traffic t CROSS JOIN Recipient r and SELECT COUNT_BIG(*) FROM Traffic t FULL JOIN Recipient r ON (1=1) they are the same.
– urlreader
Sep 20 '13 at 21:02
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Get a list of checked checkboxes in a div using jQuery
I want to get a list of names of checkboxes that are selected in a div with certain id. How would I do that using jQuery?
8...
Count table rows
...
SELECT COUNT(*) FROM fooTable;
will count the number of rows in the table.
See the reference manual.
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improve thi...
Adding 'serial' to existing column in Postgres
...int, b text);
CREATE TABLE bar (a serial, b text);
INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;
-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER...
Calculating Distance between two Latitude and Longitude GeoCoordinates
...atic double DistanceTo(double lat1, double lon1, double lat2, double lon2, char unit = 'K')
{
double rlat1 = Math.PI*lat1/180;
double rlat2 = Math.PI*lat2/180;
double theta = lon1 - lon2;
double rtheta = Math.PI*theta/180;
double dist =
Math.Sin(rlat1)*Math.Sin(rlat2) + M...
jquery change class name
... process.
Let's assume that your "External DOM Object" is an input, like a select:
Let's start with this HTML:
<body>
<div>
<select id="test">
<option>Bob</option>
<option>Sam</option>
<option>Sue</option>
<opti...