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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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First-time database design: am I overengineering? [closed]
...ds. Unless you are talking about well over a million records in your main tables you seem to be on track to having a sufficiently mainstream design that performance will not be an issue on reasonable hardware.
That said, and this relates to your question 3, with the start you have you probably s...
Android: upgrading DB version and adding new table
I've already created sqlite tables for my app, but now I want to add a new table to the database.
5 Answers
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ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
Why am I getting this database error when I update a table?
14 Answers
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T-SQL: Deleting all duplicate rows but keeping one [duplicate]
I have a table with a very large amount of rows. Duplicates are not allowed but due to a problem with how the rows were created I know there are some duplicates in this table.
I need to eliminate the extra rows from the perspective of the key columns. Some other columns may have slightly different...
MySQL - Make an existing Field Unique
I have an already existing table with a field that should be unique but is not. I only know this because an entry was made into the table that had the same value as another, already existing, entry and this caused problems.
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Insert into a MySQL table or update if exists
I want to add a row to a database table, but if a row exists with the same unique key I want to update the row.
11 Answers
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How to do an update + join in PostgreSQL?
...ATE syntax is:
[ WITH [ RECURSIVE ] with_query [, ...] ]
UPDATE [ ONLY ] table [ [ AS ] alias ]
SET { column = { expression | DEFAULT } |
( column [, ...] ) = ( { expression | DEFAULT } [, ...] ) } [, ...]
[ FROM from_list ]
[ WHERE condition | WHERE CURRENT OF cursor_name ]
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iOS 7 - How to display a date picker in place in a table view?
In WWDC 2013 video, Apple suggests displaying picker in place in a table view in iOS 7. How to insert and animate a view between table view cells?
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Rails: Using greater than/less than with a where statement
...non discrete values or columns where you can't use the + 1 strategy.
Arel table
If you want to get fancy you can make use of the Arel::Table.
User.where(User.arel_table[:id].gt(200))
will generate the SQL
"SELECT `users`.* FROM `users` WHERE (`users`.`id` > 200)"
The specifics are as foll...