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Database sharding vs partitioning
...t and it will be sequential. I did similar on DB for billion + records and sql time came to 50 millis from 30 seconds using indices etc all.
Sharding is that you host each partition on a different node/machine. Now searching inside the partitions/shards can happen in parallel.
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
I have created my tables in my SQLiteOpenHelper onCreate() but receive
15 Answers
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Replace None with NaN in pandas dataframe
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If you imported data from an SQL database, you can combine this with the answer below. This converts None (which isn't a string) to NaN. Then you can df['column'].replace(nan, "", inplace=True) if say you wanted None to be empty string.
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Reading large text files with streams in C#
... worked well for stripping apart a 19GB postgres file to translate it into sql syntax in multiple files. Thanks postgres guy who never executed my parameters correctly. /sigh
– Damon Drake
May 21 '15 at 16:24
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DateTime.Now vs. DateTime.UtcNow
...his, to store and recieve dates correctly every time, even if your IIS and SQL server are in different timezones.
– TheGeekZn
May 23 '14 at 11:34
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How can I access Google Sheet spreadsheets only with Javascript?
...ode, most API requests have JSON & easily portable to JS):
Migrating SQL data to a Sheet (code deep dive post)
Formatting text using the Sheets API (code deep dive post)
Generating slides from spreadsheet data (code deep dive post)
Those and others in the Sheets API video library
The 3rd way...
Django ManyToMany filter()
...go (version 3.0.7) seems to need it.
the above code will end up generating SQL that looks something like:
SELECT * FROM users WHERE id IN (SELECT user_id FROM userzones WHERE zone_id IN (1,2,3))
which is nice because it doesn't have any intermediate joins that could cause duplicate users to be retu...
Why are ToLookup and GroupBy different?
... With LINQ-to-Object it probably makes little difference, but with LINQ-to-SQL (or LINQ-to-EF, etc.), the grouping operation is performed on the database server rather than the client, and so you may want to do an additional filtering on the group key (which generates a HAVING clause) and then only ...
MySQL - ORDER BY values within IN()
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@Vladimir - yes, it is MySQL-specific. The question has the mysql tag.
– Ayman Hourieh
Jun 6 '09 at 1:10
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Postgresql query between date ranges
I am trying to query my postgresql db to return results where a date is in certain month and year. In other words I would like all the values for a month-year.
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