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Selecting data frame rows based on partial string match in a column
I want to select rows from a data frame based on partial match of a string in a column, e.g. column 'x' contains the string "hsa". Using sqldf - if it had a like syntax - I would do something like:
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postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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How to add text at the end of each line in Vim?
...e file, you can specify them in place of the %.
One way is to do a visual select and then type the :. It will fill in :'<,'> for you, then you type the rest of it (Notice you only need to add s/$/,/)
:'<,'>s/$/,/
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Drop data frame columns by name
...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it.
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How to create P12 certificate for iOS distribution
...hain Access where it will be matched up with the private key. You can then select the cert, and open the arrow to also select the private key and export them together as a .p12 file from Keychain Access.
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Select all 'tr' except the first one
How can I select all tr elements except the first tr in a table with CSS?
10 Answers
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Accessing an SQLite Database in Swift
...pared statement: \(errmsg)")
}
statement = nil
Prepare new statement for selecting values from table and loop through retrieving the values:
if sqlite3_prepare_v2(db, "select id, name from test", -1, &statement, nil) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
pri...
INSERT INTO vs SELECT INTO
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They do different things. Use INSERT when the table exists. Use SELECT INTO when it does not.
Yes. INSERT with no table hints is normally logged. SELECT INTO is minimally logged assuming proper trace flags are set.
In my experience SELECT INTO is most commonly used with intermediate d...
Is there a way to make text unselectable on an HTML page? [duplicate]
...an HTML UI with some text elements, such as tab names, which look bad when selected. Unfortunately, it's very easy for a user to double-click a tab name, which selects it by default in many browsers.
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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...