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Amazon SimpleDB vs Amazon DynamoDB
...best parts of
the original Dynamo design (incremental scalability, predictable high
performance) with the best parts of SimpleDB (ease of administration
of a cloud service, consistency, and a table-based data model that is
richer than a pure key-value store).
Werner's Summary suggests Dyna...
What is the difference between up-casting and down-casting with respect to class variable
...that method is declared as final or static.(Explanation Belongs to Virtual Tables Concept)
Virtual Table / Dispatch Table : An object's dispatch table will contain the addresses of the object's dynamically bound methods. Method calls are performed by fetching the method's address from the object's ...
Detect if value is number in MySQL
...
This should work in most cases.
SELECT * FROM myTable WHERE concat('',col1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
share
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how to get last insert id after insert query in codeigniter active record
...rt query (active record style) used to insert the form fields into a MySQL table. I want to get the last auto-incremented id for the insert operation as the return value of my query but I have some problems with it.
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Django dump data for a single model?
...Django dumpdata management command allows you to dump data from individual tables:
./manage.py dumpdata myapp1 myapp2.my_model
You can also separate multiple apps and models on the command line. Here's the canonical definition:
django-admin dumpdata [app_label[.ModelName] [app_label[.ModelName] ...
SQL Server: Get table primary key using sql query [duplicate]
I want to get a particular table's primary key using SQL query for SQL Server database.
10 Answers
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MySQL how to join tables on two fields
I have two tables with date and id fields. I want to join on both fields. I tried
3 Answers
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How to drop multiple columns in postgresql
I want to drop 200 columns in my table in PostgreSQL. I tried:
2 Answers
2
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Eager load polymorphic
...d is unable to build the join without additional information.
There is no table called reviewable
To solve this issue, you need to explicitly define the relationship between Review and Shop.
class Review < ActiveRecord::Base
belongs_to :user
belongs_to :reviewable, polymorphic: true
...
PadLeft function in T-SQL
I have the following table A:
17 Answers
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