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Rails migration for has_and_belongs_to_many join table
How do I do a script/generate migration to create a join table for a has_and_belongs_to_many relationship?
6 Answers
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What are the main performance differences between varchar and nvarchar SQL Server data types?
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size needed for tempdb
performance of triggers (for inserted and deleted tables that are stored in tempdb)
performance of row versioning (if using SNAPSHOT ISOLATION, since the version store is in tempdb)
ability to get new disk space when the CFO says that they just spent $1 million on a SAN last...
__FILE__, __LINE__, and __FUNCTION__ usage in C++
...on using the strings utility to extract all string-like data from the executable. Even compressed executables can be extracted. Be very mindful of what you send out to a customer site. Often times competitors are able to get their hands on your executables, even though they are not supposed to do...
Fastest way to determine if record exists
...e fastest way with the least overhead to determine if a record exists in a table or not.
11 Answers
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How can I remove duplicate rows?
... is the best way to remove duplicate rows from a fairly large SQL Server table (i.e. 300,000+ rows)?
38 Answers
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Generate GUID in MySQL for existing Data?
I've just imported a bunch of data to a MySQL table and I have a column "GUID" that I want to basically fill down all existing rows with new and unique random GUID's.
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how to generate migration to make references polymorphic
I have a Products table and want to add a column:
4 Answers
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Database design for a survey [closed]
... would be the best way to implement this in the database, specifically the tables required. The survey contains different types of questions. For example: text fields for comments, multiple choice questions, and possibly questions that could contain more than one answer (i.e. check all that apply).
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How to set auto increment primary key in PostgreSQL?
I have a table in PostgreSQL with 22 columns, and I want to add an auto increment primary key.
7 Answers
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Google Chrome Printing Page Breaks
...g to spec break-after and break-before apply only to block-level elements, table row groups, table rows (but see prose): drafts.csswg.org/css-break-3/#break-between – that means no floats or any fancy positioning tricks.
– Mikko Rantalainen
Jun 2 '16 at 11:27...