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“Large data” work flows using pandas
...ns?
What will typical operations look like. E.g. do a query on columns to select a bunch of rows and specific columns, then do an operation (in-memory), create new columns, save these.
(Giving a toy example could enable us to offer more specific recommendations.)
After that processing, then what do...
Export Postgresql table data using pgAdmin
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Just right click on a table and select "backup". The popup will show various options, including "Format", select "plain" and you get plain SQL.
pgAdmin is just using pg_dump to create the dump, also when you want plain SQL.
It uses something like this: ...
how to check the dtype of a column in python pandas
...know this is a bit of an old thread but with pandas 19.02, you can do:
df.select_dtypes(include=['float64']).apply(your_function)
df.select_dtypes(exclude=['string','object']).apply(your_other_function)
http://pandas.pydata.org/pandas-docs/version/0.19.2/generated/pandas.DataFrame.select_dtypes.h...
Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
...o be careful with booleans in Objective-C.
To sum up, only exact @YES and casted value as @((BOOL)expression) are of __NSCFBoolean type and converted to true with JSON serialization.
Any other expressions like @(expression1 && expression2) (even @(YES && YES)) are of __NSCFNumber (i...
Copy existing project with a new name in Android Studio
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I've selected the base package folder and clicked Refactor -> Rename, I got errors with "package rename" option, then I did "folder rename" option with success.
– Ismail Yavuz
May 23 '19 a...
A circular reference was detected while serializing an object of type 'SubSonic.Schema .DatabaseColu
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I think maybe selecting the ones I want may work I think the circular reference is because in Event I have IQueryable<Category> which in turn will have a IQueryable<Event>
– Jon
Jul 20 '09...
SQL- Ignore case while searching for a string
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Use something like this -
SELECT DISTINCT COL_NAME FROM myTable WHERE UPPER(COL_NAME) LIKE UPPER('%PriceOrder%')
or
SELECT DISTINCT COL_NAME FROM myTable WHERE LOWER(COL_NAME) LIKE LOWER('%PriceOrder%')
...
How do I do multiple CASE WHEN conditions using SQL Server 2008?
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Just use this one, You have to use more when they are classes.
SELECT Url='',
p.ArtNo,
p.[Description],
p.Specification,
CASE
WHEN 1 = 1 or 1 = 1
THEN 1
WHEN 2 = 2
THEN 2
WHEN 3 = 3
...
How to check if mysql database exists
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SELECT SCHEMA_NAME
FROM INFORMATION_SCHEMA.SCHEMATA
WHERE SCHEMA_NAME = 'DBName'
If you just need to know if a db exists so you won't get an error when you try to create it, simply use (From here):
CREATE DATABASE IF NO...