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Finding duplicate values in MySQL
...
Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
What is the difference between JOIN and UNION?
...t -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT 23 AS bah...
Google Authenticator implementation in Python
...cret (it must be correct parameter for base64.b32decode()) - preferably 16-char (no = signs), as it surely worked for both script and Google Authenticator.
Use get_hotp_token() if you want one-time passwords invalidated after each use. In Google Authenticator this type of passwords i mentioned as b...
Unable to find valid certification path to requested target - error even after cert imported
... main(String[] args) throws Exception {
String host;
int port;
char[] passphrase;
if ((args.length == 1) || (args.length == 2)) {
String[] c = args[0].split(":");
host = c[0];
port = (c.length == 1) ? 443 : Integer.parseInt(c[1]);
String p = (args.leng...
How can I select rows with most recent timestamp for each key value?
...r data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
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jQuery get value of selected radio button
The problem statement is simple. I need to see if user has selected a radio button from a radio group. Every radio button in the group share same id.
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How to convert a string of numbers to an array of numbers?
... the string so x=>+x (which is even shorter than the Number function (5 chars instead of 6)) is equivalent to :
function(x){return parseInt(x,10)}// version from techfoobar
(x)=>{return parseInt(x)} // lambda are shorter and parseInt default is 10
(x)=>{return +x} ...
SQL Server: Get table primary key using sql query [duplicate]
...
I also found another one for SQL Server:
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE OBJECTPROPERTY(OBJECT_ID(CONSTRAINT_SCHEMA + '.' + QUOTENAME(CONSTRAINT_NAME)), 'IsPrimaryKey') = 1
AND TABLE_NAME = 'TableName' AND TABLE_SCHEMA = 'Schema'
...
Convert hyphens to camel case (camelCase)
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@wolfram77, You include multiple dashes/space characters in the regexp, then uppercase the second character of the match, meaning if the second character is a space or dash, it is the one getting uppercased. How about this: var camelCased = myString.replace(/(-+|\s+)\w/g...
Modifying location.hash without page scrolling
... load
if(document.location.hash){
$("#buttons li a").removeClass('selected');
s=$(document.location.hash.replace("btn_","")).addClass('selected').attr("href").replace("javascript:","");
eval(s);
}
//Click a button to change the hash
$("#buttons li a").click(function()...