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How do I get a list of all the duplicate items using pandas in python?
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Method #1: print all rows where the ID is one of the IDs in duplicated:
>>> import pandas as pd
>>> df = pd.read_csv("dup.csv")
>>> ids = df["ID"]
>>> df[ids.isin(ids[ids.duplicated()])].sort("ID")
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How to get CSS to select ID that begins with a string (not in Javascript)?
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[id^=product]
^= indicates "starts with". Conversely, $= indicates "ends with".
The symbols are actually borrowed from Regex syntax, where ^ and $ mean "start of string" and "end of string" respectively.
See the specs for full information.
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jquery IDs with spaces
Does anyone know how to select an item in the DOM by ID with jQuery, when that ID has a space?
11 Answers
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Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
5 Answers
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SQL join: selecting the last records in a one-to-many relationship
...omer. I want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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Django select only rows with duplicate field values
suppose we have a model in django defined as follows:
5 Answers
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Rails find record with zero has_many records associated [duplicate]
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Bah, found it here: https://stackoverflow.com/a/5570221/417872
City.includes(:photos).where(photos: { city_id: nil })
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LEFT JOIN only first row
I read many threads about getting only the first row of a left join, but, for some reason, this does not work for me.
6 Ans...
Can table columns with a Foreign Key be NULL?
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Yes, you can enforce the constraint only when the value is not NULL. This can be easily tested with the following example:
CREATE DATABASE t;
USE t;
CREATE TABLE parent (id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=INNODB;
CREATE TABLE...
Remove by _id in MongoDB console
In the MongoDB console how can I remove a record by id? Here's my collection :
11 Answers
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