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SQL Query to concatenate column values from multiple rows in Oracle
...ted string exceeds 4000 characters( limit for VARCHAR2 in SQL ), the below error is thrown, which is difficult to manage in Oracle versions upto 12.1
ORA-01489: result of string concatenation is too long
A new feature added in 12cR2 is the ON OVERFLOW clause of LISTAGG.
The query including t...
Reconnection of Client when server reboots in WebSocket
...lt:
break;
}
};
websocket.onerror = function(ev){};
websocket.onclose = function(ev) { init(); };
}
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VC菜单命令详解(文件打开、保存与关闭) - C/C++ - 清泛网 - 专注C/C++及内核技术
...射到CWinApp::OnFileOpen函数,它将执行以下几个步骤:
1、提示用户选择一个文件;
2、调用虚函数CDocument::OnOpenDocument,CDocument::OnOpenDocument打开文件,调用CDocument::DeleteContents,并且构造一个CArchive对象。随后调用document的Serialize函...
Search for executable files using find command
...
Error find: invalid mode ‘+111’ on findutils 4.5.11 4.fc20.
– sourcejedi
Jul 17 '14 at 10:31
...
How to add hyperlink in JLabel?
...Desktop.getDesktop().browse(uri);
} catch (IOException e) { /* TODO: error handling */ }
} else { /* TODO: error handling */ }
}
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Get type of all variables
...character
typeof(3 + 四) #R pukes on unicode error
typeof(iconv("a", "latin1", "UTF-8")) #UTF-8 characters character
typeof(5 == 5) #result of a comparison: logical
How to get the class of a variable you have in R
The R function class ...
VC窗口刷新InvalidateRect和UpdateWindow - C/C++ - 清泛网 - 专注C/C++及内核技术
...对话框或消息框;菜单下拉出来,然后被释放;显示工具提示消息。
在某些情况下,Windows总是一定保存它所覆盖的显示区域,然后恢复它。这些情况是:鼠标光标穿越显示区域;图标拖过显示区域。
有时候应用也需要能够主...
Set every cell in matrix to 0 if that row or column contains a 0
... row and column are both 1s.
Coding it will be tricky to avoid off-by-one errors etc but it should work in one pass.
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Understanding the map function
...your function should look for None and handle them, otherwise you will get errors. In Python 3 map() will stop after finishing with the shortest list. Also, in Python 3, map() returns an iterator, not a list.
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Find index of last occurrence of a substring in a string
... recent call last):
File "<stdin>", line 1, in <module>
ValueError: substring not found
The difference is when the substring is not found, rfind() returns -1 while rindex() raises an exception ValueError (Python2 link: ValueError).
If you do not want to check the rfind() return cod...