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How to apply a function to two columns of Pandas dataframe
...pose I have a df which has columns of 'ID', 'col_1', 'col_2' . And I define a function :
12 Answers
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Database Design for Tagging
How would you design a database to support the following tagging features:
12 Answers
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How to detect if a stored procedure already exists
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If you DROP and CREATE the procedure, you will loose the security settings. This might annoy your DBA or break your application altogether.
What I do is create a trivial stored procedure if it doesn't exist yet. After that, you can ALTER the stored procedure to your liking.
IF object_id('Yo...
T-SQL: Deleting all duplicate rows but keeping one [duplicate]
... a problem with how the rows were created I know there are some duplicates in this table.
I need to eliminate the extra rows from the perspective of the key columns. Some other columns may have slightly different data but I do not care about that. I still need to keep one of these rows however. SE...
jQuery: select an element's class and id at the same time?
I've got some links that I want to select class and id at the same time.
6 Answers
6
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MySQL Error 1093 - Can't specify target table for update in FROM clause
I have a table story_category in my database with corrupt entries. The next query returns the corrupt entries:
16 Answers...
Pythonic way to create a long multi-line string
I have a very long query. I would like to split it in several lines in Python. A way to do it in JavaScript would be using several sentences and joining them with a + operator (I know, maybe it's not the most efficient way to do it, but I'm not really concerned about performance in this stage, jus...
Why does MYSQL higher LIMIT offset slow the query down?
Scenario in short: A table with more than 16 million records [2GB in size]. The higher LIMIT offset with SELECT, the slower the query becomes, when using ORDER BY *primary_key*
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1052: Column 'id' in field list is ambiguous
...have 2 tables. tbl_names and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
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You can't specify target table for update in FROM clause
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The problem is that MySQL, for whatever inane reason, doesn't allow you to write queries like this:
UPDATE myTable
SET myTable.A =
(
SELECT B
FROM myTable
INNER JOIN ...
)
That is, if you're doing an UPDATE/INSERT/DELETE on a table, you can't referen...