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What are the differences between ArrayList and Vector?
... get the element at a particular location from Vector we use elementAt(int index) function. This function name is very lengthy.
In place of this in ArrayList we have get(int index) which is very
easy to remember and to use.
Similarly to replace an existing element with a new element in Vector we use...
What do the result codes in SVN mean?
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SVN status columns
$ svn status
L index.html
The output of the command is split into six columns, but that is not obvious because sometimes the columns are empty. Perhaps it would have made more sense to indicate the empty columns with dashes, the way ls -l...
Add to Array jQuery
....
var myArray = [];
myArray.push("foo");
// myArray now contains "foo" at index 0.
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Get record counts for all tables in MySQL database
...ount FROM my_schema.host UNION
SELECT "ndb_binlog_index" AS table_name, COUNT(*) AS exact_row_count FROM my_schema.ndb_binlog_index UNION
Copy and paste except for the last UNION to get nice output like,
+------------------+-----------------+
| table_name | exact_r...
Random record in ActiveRecord
...that using offset is very slow with large dataset, since it actually needs index scan (or table scan, in case clustered index is used like InnoDB). In other words, it's O(N) operation but "WHERE id >= #{rand_id} ORDER BY id ASC LIMIT 1" is O(log N), which is much faster.
– k...
SQL “select where not in subquery” returns no results
...mortech's answer and @rexem's comments.
If either Table1 or Table2 is not indexed on commonID, you get a table scan but @patmortech's query is still twice as fast (for a 100K row master table).
If neither are indexed on commonID, you get two table scans and the difference is negligible.
If both a...
Change type of varchar field to integer: “cannot be cast automatically to type integer”
...f the error still occurs, then it may be related not to column values, but indexes over this column or column default values might fail typecast. Indexes need to be dropped before ALTER COLUMN and recreated after. Default values should be changed appropriately.
...
How to force file download with PHP
...
Display your file first and set its value into url.
index.php
<a href="download.php?download='.$row['file'].'" title="Download File">
download.php
<?php
/*db connectors*/
include('dbconfig.php');
/*function to set your files*/
function output_file($file, $name, $...
Create subdomains on the fly with .htaccess (PHP)
...riteEngine on
RewriteCond %{HTTP_HOST} ^[^.]+\.example\.com$
RewriteRule !^index\.php$ index.php [L]
Inside the index.php you can than extract the subdomain using:
if (preg_match('/^([^.]+)\.example\.com$/', $_SERVER['HTTP_HOST'], $match)) {
var_dump($match[1]);
}
But all this requires that...
HTML5 Canvas Resize (Downscale) Image High Quality?
... = Math.floor(sh * scale); // target image height
var sx = 0, sy = 0, sIndex = 0; // source x,y, index within source array
var tx = 0, ty = 0, yIndex = 0, tIndex = 0; // target x,y, x,y index within target array
var tX = 0, tY = 0; // rounded tx, ty
var w = 0, nw = 0, wx = 0, nwx = 0...