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How to Store Historical Data
... records will go in FOO_Hist. Many different fields in FOO can be updated by the user, so I want to keep an accurate account of everything updated. FOO_Hist holds the exact same fields as FOO with the exception of an auto-incrementing HIST_ID. Every time FOO is updated, I perform an insert statem...
How do I associate a Vagrant project directory with an existing VirtualBox VM?
...o VBoxManage list vms which will list every VM that VirtualBox knows about by its name and UUID. Then manually create a .vagrant file in the same directory as your Vagrantfile and fill in the contents properly.
Run vagrant status to ensure that Vagrant picked up the proper changes.
Note: This is n...
How to delete duplicate rows in SQL Server?
...3], [col4], [col5], [col6], [col7],
RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1)
FROM dbo.Table1
)
DELETE FROM CTE WHERE RN > 1
DEMO (result is different; I assume that it's due to a typo on your part)
COL1 COL2 COL3 COL4 COL5 COL6 COL7
john 1 1...
how to exclude null values in array_agg like in string_agg using postgres?
If I use array_agg to collect names, I get my names separated by commas, but in case there is a null value, that null is also taken as a name in the aggregate. For example :
...
SQLite - UPSERT *not* INSERT or REPLACE
...PSERT is not standard SQL. UPSERT in SQLite follows the syntax established by PostgreSQL.
GOOD but tendous: This will update 2 of the columns.
When ID=1 exists, the NAME will be unaffected.
When ID=1 does not exist, the name will be the default (NULL).
INSERT OR REPLACE INTO Employee (id, role,...
SQL Server add auto increment primary key to existing table
...<Id> = x.New_Id
FROM (
SELECT <Id>, ROW_NUMBER() OVER (ORDER BY <tablekey>) AS New_Id
FROM <tablename>
) x
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How can foreign key constraints be temporarily disabled using T-SQL?
..._NAME(RKEYID, RKEY) AS REFERENCED_COLUMN_NAME
FROM SYSFOREIGNKEYS
ORDER BY TABLE_NAME, CONSTRAINT_NAME,REFERENCED_TABLE_NAME, KEYNO
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Compare two DataFrames and output their differences side-by-side
...ted Mar 30 '18 at 6:19
Roobie Nuby
99499 silver badges1717 bronze badges
answered Jul 17 '16 at 13:12
James Ow...
django order_by query set, ascending and descending
How can I order by descending my query set in django by date?
11 Answers
11
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Include intermediary (through model) in responses in Django Rest Framework
... serializer to pull out the bits you want to display.
EDIT: as commented by @bryanph, serializers.field was renamed to serializers.ReadOnlyField in DRF 3.0, so this should read:
class MembershipSerializer(serializers.HyperlinkedModelSerializer):
id = serializers.ReadOnlyField(source='group.i...