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Can you get the column names from a SqlDataReader?
...GetName(i));
}
or
var columns = Enumerable.Range(0, reader.FieldCount).Select(reader.GetName).ToList();
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How to write a scalable Tcp/Ip based server
... to doubt these indicative figures.
IOCP versus thread-per-connection or 'select' primitives
The reason you want to use a mechanism that uses IOCP under the hood is that it uses a very low-level Windows thread pool that does not wake up any threads until there is actual data on the IO channel that...
Python in Xcode 4+?
...
In the menu bar, click “File” → “New” → “New Project…”.
Select “Other” in the left pane, then "External Build System" in the right page, and next click "Next".
Enter the product name, organization name, or organization identifier.
For the “Build Tool” field, type in /usr/l...
Sublime Text 2: Trim trailing white space on demand
...way that uses no plugins or settings and works in most situations.
Multi-Select and move cursor to the end of every line
Hold CTRL-Shift, Press Left, Right
The spaces and tabs at the end of the lines should now be selected. Press Delete or Backspace
Note - Special characters such as ( and + may ...
AngularJS: how to implement a simple file upload with multipart form?
...tags so you have to do it in a "native-way" that pass the all (eventually) selected files from the user.
controller
$scope.uploadFile = function(files) {
var fd = new FormData();
//Take the first selected file
fd.append("file", files[0]);
$http.post(uploadUrl, fd, {
withCr...
Selecting multiple classes with jQuery
I’ve had a good look and can’t seem to find out how to select all elements matching certain classes in one jQuery selector statement such as this:
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How can I iterate through the unicode codepoints of a Java String?
So I know about String#codePointAt(int) , but it's indexed by the char offset, not by the codepoint offset.
4 Answers
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How do I delete a fixed number of rows with sorting in PostgreSQL?
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You could try using the ctid:
DELETE FROM logtable
WHERE ctid IN (
SELECT ctid
FROM logtable
ORDER BY timestamp
LIMIT 10
)
The ctid is:
The physical location of the row version within its table. Note that although the ctid can be used to locate the row version very quickly,...
How to get Top 5 records in SqLite?
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SELECT * FROM Table_Name LIMIT 5;
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Modifying a subset of rows in a pandas dataframe
...The df.A==0 expression creates a boolean series that indexes the rows, 'B' selects the column. You can also use this to transform a subset of a column, e.g.:
df.loc[df.A==0, 'B'] = df.loc[df.A==0, 'B'] / 2
I don't know enough about pandas internals to know exactly why that works, but the basic is...