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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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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
14
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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...
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...
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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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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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...
How can I change the table names when using ASP.NET Identity?
... "Individual User Accounts" for authentication. This creates the following tables:
7 Answers
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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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