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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
4
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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 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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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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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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Convert objective-c typedef to its string equivalent
...ms are really just glorified integer constants. You'll have to generate a table of names yourself (or with some preprocessor abuse). For example:
// In a header file
typedef enum FormatType {
JSON,
XML,
Atom,
RSS
} FormatType;
extern NSString * const FormatType_toString[];
// In...
Scraping html tables into R data frames using the XML package
How do I scrape html tables using the XML package?
4 Answers
4
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Can I restore a single table from a full mysql mysqldump file?
I have a mysqldump backup of my mysql database consisting of all of our tables which is about 440 megs. I want to restore the contents of just one of the tables from the mysqldump. Is this possible? Theoretically, I could just cut out the section that rebuilds the table I want but I don't even know ...
What are the main performance differences between varchar and nvarchar SQL Server data types?
...)
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...
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...