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Fastest check if row exists in PostgreSQL
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How about simply:
select 1 from tbl where userid = 123 limit 1;
where 123 is the userid of the batch that you're about to insert.
The above query will return either an empty set or a single row, depending on whether there are records with the given userid.
If this turns o...
Grep characters before and after match?
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3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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How do I fetch a single model in Backbone?
...ers with the hashbang in your URL like so, http://www.mydomain.com/#clocks/123 , but it should work even if you haven't yet.
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...red Jul 15 '13 at 22:16
Thejoker123Thejoker123
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cout保留两位小数输出 - C/C++ - 清泛网 - 专注C/C++及内核技术
...precision函数需要引入该头文件
int main() {
double dval = 123.456789;
// C风格
printf("in C: %.2f\n", dval);
// cout固定输出几位（整数+小数一起）
std::cout << std::setprecision(5) << dval << std::endl;
// cout固定输出2位小数，整数...
App Inventor 2 Clipboard 拓展：实现剪贴板的复制粘贴功能 · App Inventor 2 中文网
...基于 TaifunClipboard 拓展 开发。
.aix 拓展下载：
cn.fun123.Clipboard.aix
demo程序下载：
Clipboard.aia
使用方法
属性及方法很简单，默认操作成功后显示提示信息，SuppressToast设置为 假 后，则不显示提示信息。
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Array initialization syntax when not in a declaration
...answered Mar 25 '16 at 4:04
user123user123
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Python equivalent of D3.js
...wered Oct 10 '13 at 19:28
sk8asd123sk8asd123
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Eclipse RCP Plug-in开发自学教程（Eclipse3.6） - 文档下载 - 清泛网 - ...
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11.1 简介 ........................................................................................................................................123
11.2 添加透视图 .................................................
Checking if object is empty, works with ng-show but not from controller?
...wered May 8 '14 at 22:21
testing123testing123
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