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SQLite add Primary Key
I created a table in Sqlite by using the CREATE TABLE AS syntax to create a table based on a SELECT statement. Now this table has no primary key but I would like to add one.
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Difference between left join and right join in SQL Server [duplicate]
I know about joins in SQL Server.
9 Answers
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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
I have a table with existing data. Is there a way to add a primary key without deleting and re-creating the table?
4 Answer...
SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
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update q
set q.QuestionID = a.QuestionID
from QuestionTrackings q
inner join QuestionAnswers a
on q.AnswerID = a.AnswerID
where q.QuestionID is null -- and other conditions you might want
I recommend to check what the result set to update is before running the update (same query, j...
find vs find_by vs where
I am new to rails. What I see that there are a lot of ways to find a record:
12 Answers
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Cannot delete or update a parent row: a foreign key constraint fails
When doing:
18 Answers
18
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ssh “permissions are too open” error
I had a problem with my mac where I couldn't save any kind of file on the disk anymore.
I had to reboot OSX lion and reset the permissions on files and acls.
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How do I update an entity using spring-data-jpa?
Well the question pretty much says everything. Using JPARepository how do I update an entity?
9 Answers
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Rails auto-assigning id that already exists
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Rails is probably using the built-in PostgreSQL sequence. The idea of a sequence is that it is only used once.
The simplest solution is to set the sequence for your company.id column to the highest value in the table with a query like this:
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How to Create a circular progressbar in Android which rotates on it?
I am trying to create a rounded progressbar. This is what I want to achieve
12 Answers
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