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How to convert a table to a data frame
I have a table in R that has str() of this:
5 Answers
5
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Best design for a changelog / auditing database table? [closed]
I need to create a database table to store different change log/auditing
(when something was added, deleted, modified, etc). I don't need to store particularly detailed info, so I was thinking something along the lines of:
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How to drop SQL default constraint without knowing its name?
...t and dynamically execute it.
declare @schema_name nvarchar(256)
declare @table_name nvarchar(256)
declare @col_name nvarchar(256)
declare @Command nvarchar(1000)
set @schema_name = N'MySchema'
set @table_name = N'Department'
set @col_name = N'ModifiedDate'
select @Command = 'ALTER TABLE ' + @sc...
Why is a div with “display: table-cell;” not affected by margin?
I have div elements next to each other with display: table-cell; .
4 Answers
4
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MySQL 'create schema' and 'create database' - Is there any difference
...EATE SCHEMA" command, and it served to introduce
multiple name spaces for table and view names. All tables and views were
created within a "schema". I do not know whether that version defined
some cross-schema access to tables and views, but I assume it did.
AFAIR, no product (at least back then)...
Group by & count function in sqlalchemy
... is better to use func.count():
from sqlalchemy import func
session.query(Table.column, func.count(Table.column)).group_by(Table.column).all()
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Rails has_and_belongs_to_many migration
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You need to add a separate join table with only a restaurant_id and user_id (no primary key), in alphabetical order.
First run your migrations, then edit the generated migration file.
Rails 3
rails g migration create_restaurants_users_table
Rails 4:
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Using a Single Row configuration table in SQL Server database. Bad idea?
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I have done this two ways in the past - a single row table and a key/value pair table - and there are positives and negatives to each approach.
Single Row
positive: the values are stored in the correct type
positive: it is easier to deal with in code (due to the above)
positiv...
How can I temporarily disable a foreign key constraint in MySQL?
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Can I just disable FOREIGN_KEY_CHECKS for a single table?
– jDub9
Dec 20 '18 at 13:53
@Pacerie...
Get list of all tables in Oracle?
How do I query an Oracle database to display the names of all tables in it?
23 Answers
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