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What is the difference between single and double quotes in SQL?
...ould be more readable as product_id, so you use either of the following:
SELECT PRODUCT.id AS product_id
SELECT PRODUCT.id 'product_id'
Either works in Oracle, SQL Server, MySQL… but I know some have said that the TOAD IDE seems to give some grief when using the single quotes approach.
You do...
XPath: How to select elements based on their value?
...st thing is when using [], there are only two types of data:
[number] to select a node from node-set
[bool] to filter a node-set from node-set
In this case, the value is evaluated to boolean by function boolean(), and there is a rule:
Filters are always evaluated with respect to a context.
...
Why does MYSQL higher LIMIT offset slow the query down?
...h more than 16 million records [2GB in size]. The higher LIMIT offset with SELECT, the slower the query becomes, when using ORDER BY *primary_key*
...
How can I set the color of a selected row in DataGrid
The default background color of a selected row in DataGrid is so dark that I can't read it. Is there anyway of overriding it?
...
Is there a way to select sibling nodes?
For some performance reasons, I am trying to find a way to select only sibling nodes of the selected node.
13 Answers
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Nexus 7 not visible over USB via “adb devices” from Windows 7 x64
...he Nexus, or undoubtedly any other device. Not exactly obvious, but if you select the second option "Camera (PTP)" the device is available for debugging (the lesson is ignore the camera, and focus on the protocol PTP).
This configuration is persistent, and I'm guessing that with a brand new device...
Correct way to add external jars (lib/*.jar) to an IntelliJ IDEA project
...ps for adding external jars in IntelliJ IDEA:
Click File from the toolbar
Select Project Structure option (CTRL + SHIFT + ALT + S on Windows/Linux, ⌘ + ; on Mac OS X)
Select Modules at the left panel
Select Dependencies tab
Select + icon
Select 1 JARs or directories option
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How do I copy to the clipboard in JavaScript?
...
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand('copy');
var msg = successful ? 'successful' : 'unsuccessful';
console.log('Fallback: Copying text command was ' + msg);
} catch (err) {
consol...
How can I suppress column header output for a single SQL statement?
...in batch (using the mysql command-line binary). I want one of my several SELECT statements to not print the column headers, just the selected records. Is this possible?
...
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...