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get list of pandas dataframe columns based on data type
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If you are just selecting columns by data type, then this answer is obsolete. Use select_dtypes instead
– Ted Petrou
Nov 3 '17 at 16:58
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How to list the tables in a SQLite database file that was opened with ATTACH?
...quently, if you used
ATTACH some_file.db AS my_db;
then you need to do
SELECT name FROM my_db.sqlite_master WHERE type='table';
Note that temporary tables don't show up with .tables either: you have to list sqlite_temp_master for that:
SELECT name FROM sqlite_temp_master WHERE type='table';
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The current branch is not configured for pull No value for key branch.master.merge found in configur
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To fix this problem in Eclipse, open the Windows menu and select Show View / Other / Git Repositories.
From the Git Repositories tab:
expand your local repository
right click on Remote
click on Create Remote...
Remote name = origin
next to IRI press the Change button
CTRL+SPACE o...
How to report an error from a SQL Server user-defined function
... For an inline-table-valued-function where the RETURN is a simple select, this alone doesn't work because nothing is returned - not even null, and in my case I wanted to throw an error when nothing was found. I didn't want to break down the inline function into a multi-statment one for obv...
Auto select file in Solution Explorer from its open tab
...times, I find myself right-clicking on a tab title and searching for Show/Select/Scroll-to this file in Solution Explorer , and I can't find it.
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Android Spinner : Avoid onItemSelected calls during initialization
...droid application with a Spinner and a TextView . I want to display the selected item from the Spinner's drop down list in the TextView. I implemented the Spinner in the onCreate method so when I'm running the program, it shows a value in the TextView (before selecting an item from the drop d...
How do I set up IntelliJ IDEA for Android applications?
...Program Files\Java\jdk{version}
Choose a New platform ( if there's not one selected ) , the SDK platform is the android platform at C:\Program Files\Android\android-sdk-windows.
Choose the android version.
Now you can write your program.
Compiling:
Near the Run button you need to select the drop...
How to return result of a SELECT inside a function in PostgreSQL?
... bigint
, ratio bigint) AS
$func$
BEGIN
RETURN QUERY
SELECT t.txt
, count(*) AS cnt -- column alias only visible inside
, (count(*) * 100) / _max_tokens -- I added brackets
FROM (
SELECT t.txt
FROM token t
WHERE t.charty...
PostgreSQL create table if not exists
..._mytable()
RETURNS void
LANGUAGE plpgsql AS
$func$
BEGIN
IF EXISTS (SELECT FROM pg_catalog.pg_tables
WHERE schemaname = 'myschema'
AND tablename = 'mytable') THEN
RAISE NOTICE 'Table myschema.mytable already exists.';
ELSE
CREATE TABLE myschema...
Count(*) vs Count(1) - SQL Server
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The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...