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How to select following sibling/xml tag using xpath
... we are interested in. In this case you can omit ./ . Also, if you want to select the immediate following sibling, use: following-sibling::td[1], otherwise, if there are more than one following siblings, all will be selected.
– Dimitre Novatchev
Jan 23 '16 at 2...
How do I clear all options in a dropdown box?
...
You can use the following to clear all the elements.
var select = document.getElementById("DropList");
var length = select.options.length;
for (i = length-1; i >= 0; i--) {
select.options[i] = null;
}
...
How do I get SUM function in MySQL to return '0' if no values are found?
...
Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nul...
How to make connection to Postgres via Node.js
...values($1, $2)", ['John', x]);
x = x - 1;
}
var query = client.query("SELECT * FROM junk");
//fired after last row is emitted
query.on('row', function(row) {
console.log(row);
});
query.on('end', function() {
client.end();
});
//queries can be executed either via text/parameter val...
Select rows of a matrix that meet a condition
...20, ncol = 4)
colnames(m) <- letters[1:4]
The following command will select the first row of the matrix above.
subset(m, m[,4] == 16)
And this will select the last three.
subset(m, m[,4] > 17)
The result will be a matrix in both cases.
If you want to use column names to select columns...
jQuery count child elements
...
You can use .length with just a descendant selector, like this:
var count = $("#selected li").length;
If you have to use .children(), then it's like this:
var count = $("#selected ul").children().length;
You can test both versions here.
...
find filenames NOT ending in specific extensions on Unix?
...
Or without ( and the need to escape it:
find . -not -name "*.exe" -not -name "*.dll"
and to also exclude the listing of directories
find . -not -name "*.exe" -not -name "*.dll" -not -type d
or in positive logic ;-)
find . -not -nam...
PostgreSQL error 'Could not connect to server: No such file or directory'
...n your postgres directory, probably /usr/local/var/postgres/
remove this and start server.
Check - https://github.com/mperham/lunchy is a great wrapper for launchctl.
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...
Read binary file as string in Ruby
I need an easy way to take a tar file and convert it into a string (and vice versa). Is there a way to do this in Ruby? My best attempt was this:
...
PostgreSQL: insert from another table
...
Just supply literal values in the SELECT:
INSERT INTO TABLE1 (id, col_1, col_2, col_3)
SELECT id, 'data1', 'data2', 'data3'
FROM TABLE2
WHERE col_a = 'something';
A select list can contain any value expression:
But the expressions in the select list do...