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Questions - multi-index

Avoid filesort in simple filtered ordered query

I have a simple table: CREATE TABLE `user_values` ( `id` bigint NOT NULL AUTO_INCREMENT, `user_id` bigint NOT NULL, `value` varchar(100) NOT NULL, PRIMARY KEY (`id`), KEY `user_id` (`user_id...
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bkr879

mysql

indexing

multi-index

Votes: 0

Answers: 3

Latest Answer

MySQL will most likely use index for the query (unless the user_id's in the query covers most of the rows). The "filesort" happens in memory (it's really not a filesort), and is used to sort...
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slaakso

Pandas multiindex filter if duplicated, but keep first duplicated

Assume I have a multiindex Pandas data frame with three indices (Date, Product, Country) arrays = [['2021-12-30', '2021-12-30', '2021-12-30', '2021-12-31', '2021-12-31', '2021-12-31', '2022-01-01', '2...
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W. Walter

python

pandas

multi-index

Votes: 0

Answers: 0

Accessing and overwriting Multiindex df data

I'm trying to multiply all the values of the following multiindex df for which the first multiindex equals Property_2 with a scalar: (index_1,index_2) Col1 Property_1 A 1 B ...
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Milan

python

pandas

dataframe

multi-index

Votes: 0

Answers: 1

Latest Answer

That's because the indices don't match. One way to get around the issue is to assign the underlying numpy array: df.loc['Property_2', 'Col1'] = df.loc['Property_2', 'Col1'].mul(0.01).to_numpy() or yo...
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user7864386

Pandas: Conditionally dropping columns based on same values throughout the column in MultiIndex dataframe

I have a dataframe as below: data = {('5105', 'Open'): [1.99,1.98,1.99,2.05,2.15], ('5105', 'Adj Close'): [1.92,1.92,1.96,2.07,2.08], ('5229', 'Open'): [0.01]*5, ('5229', 'Adj ...
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user16836078

python

python-3.x

pandas

dataframe

multi-index

Votes: 0

Answers: 4

Latest Answer

Try with nunique df = df.loc[:,~(df.nunique()==1).values] Out[125]: 5105 7076 Open Adj Close Open Adj Close 0 1.99 1.92 1.02 0.90 1 1.98 1.92 1.01 ...
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