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what is the right way to treat Python argparse.Namespace() as a dictionary?
...dictionary should not be modified: the effects on the corresponding symbol table are undefined." Which may only refer to the behavior of vars() (which is either locals() or globals()), but I'm not really sure.
– user395760
Jun 1 '13 at 23:43
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Newline in markdown table?
I have the following cells in a markdown table:
4 Answers
4
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Add unique constraint to combination of two columns
I have a table and, somehow, the same person got into my Person table twice. Right now, the primary key is just an autonumber but there are two other fields that exist that I want to force to be unique.
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data.frame rows to a list
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@AaronMcDaid Or data.table::rbindlist(). If your original data frame was large, the speed gains will be significant.
– Empiromancer
Jul 12 '16 at 22:04
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Escape single quote character for use in an SQLite query
I wrote the database schema (only one table so far), and the INSERT statements for that table in one file. Then I created the database as follows:
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How to check existence of user-define table type in SQL Server 2008?
I have a user-defined table type. I want to check it's existence before editing in a patch using OBJECT_ID(name, type) function.
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MySQL Great Circle Distance (Haversine formula)
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@FosAvance Yes, this query would work if you have markers table with id, lan and lng fields.
– Pavel Chuchuva
Mar 29 '14 at 23:08
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Simulating group_concat MySQL function in Microsoft SQL Server 2005?
...to do this. Lots of ideas out there, though.
Best one I've found:
SELECT table_name, LEFT(column_names , LEN(column_names )-1) AS column_names
FROM information_schema.columns AS extern
CROSS APPLY
(
SELECT column_name + ','
FROM information_schema.columns AS intern
WHERE extern.table_n...
How do I make a composite key with SQL Server Management Studio?
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Open the design table tab
Highlight your two INT fields (Ctrl/Shift+click on the grey blocks in the very first column)
Right click -> Set primary key
share
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SQL join: selecting the last records in a one-to-many relationship
Suppose I have a table of customers and a table of purchases. Each purchase belongs to one customer. 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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