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What is the Oracle equivalent of SQL Server's IsNull() function?
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Instead of ISNULL(), use NVL().
T-SQL:
SELECT ISNULL(SomeNullableField, 'If null, this value') FROM SomeTable
PL/SQL:
SELECT NVL(SomeNullableField, 'If null, this value') FROM SomeTable
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Freeze screen in chrome debugger / DevTools panel for popover inspection?
...e
Open the dev console - F12 on Windows/Linux or option + ⌘ + J on macOS
Select the Sources tab in chrome inspector
In the web browser window, hover over the desired element to initiate the popover
Hit F8 on Windows/Linux (or fn + F8 on macOS) while the popover is showing. If you have clicked anyw...
Difference between save and saveAndFlush in Spring data jpa
... flush mode AUTO and you are using your application to first save and then select the data again, you will not see a difference in bahvior between save() and saveAndFlush() because the select triggers a flush first. See the documention.
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How to Correctly Use Lists in R?
...dresses the question of the difference between [] and [[]].
In short [[]] selects a single item from a list and [] returns a list of the selected items. In your example, x = list(1, 2, 3, 4)' item 1 is a single integer but x[[1]] returns a single 1 and x[1] returns a list with only one value.
>...
How to set Oracle's Java as the default Java in Ubuntu?
...There are 2 choices for the alternative java (providing /usr/bin/java).
Selection Path Priority Status
------------------------------------------------------------
* 0 /opt/java/jdk1.8.0_05/bin/java 20000 auto mode
1...
How do I launch the Android emulator from the command line?
...pment you just use the same Ant script you used to build the project, just select install target. However, you can install the application manually using command adb install <path-to-your-APK>.
Now switch to emulator and launch your application like on any normal device, through the launcher. ...
how to POST/Submit an Input Checkbox that is disabled?
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A bit old, but as sidenote: If you use <select> or <textfield> or other HTML elements that support the disabled attribute, you can select them and enable all with: $( "*:disabled" ).removeAttr("disabled");
– Gusstavv Gil
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App Inventor 2 蓝牙遥控教程 - 经典蓝牙与BLE控制智能硬件 · App Inventor 2 中文网
...选择器1.AfterPicking() {
if 蓝牙客户端1.Connect(列表选择器1.Selection) {
标签_状态.Text = "已连接：" + 列表选择器1.Selection
蓝牙客户端1.Secure = true
} else {
标签_状态.Text = "连接失败，请重试"
}
}
说明：
蓝牙客户端1.Addres...
rvm installation not working: “RVM is not a function”
...64 bit - nerdy gnat or whatever) - I kept getting
"RVM is not a function, selecting rubies with 'rvm use ...' will not work."
Before, I got the message, but 'rvm 1.9.3-p0@rails321' would work. Now, it wouldn't work - you couldn't change gemsets at all.
Nothing worked, until I found this - make th...
Is there a best practice for generating html with javascript
...$.template('<div><img src="${url}" />${name}</div>');
$(selector).append( t , {
url: jsonObj.url,
name: jsonObj.name
});
I say go the cool route (and better performing, more maintainable), and use templating.
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