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How can I create a unique constraint on my column (SQL Server 2008 R2)?
...@WhiteIsland - You should see it in SSMS object Explorer if you expand the table and look under "Keys"
– Martin Smith
Mar 3 '11 at 18:43
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How do I retrieve my MySQL username and password?
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Stop the MySQL process.
Start the MySQL process with the --skip-grant-tables option.
Start the MySQL console client with the -u root option.
List all the users;
SELECT * FROM mysql.user;
Reset password;
UPDATE mysql.user SET Password=PASSWORD('[password]') WHERE User='[username]';
But DO NO...
How to create a multi-tenant database with shared table structures?
..., it looks like the shared-database, single-schema approach is the most suitable. The fact that you'll be storing just about 50Mb per tenant, and that there will be no per-tenant add-ons, makes this approach even more appropriate.
The MSDN article cited above mentions three security patterns that t...
What's the difference between belongs_to and has_one?
...oreign key is. We can say that a User "has" a Profile because the profiles table has a user_id column. If there was a column called profile_id on the users table, however, we would say that a Profile has a User, and the belongs_to/has_one locations would be swapped.
here is a more detailed explanat...
Reshaping data.frame from wide to long format
I have some trouble to convert my data.frame from a wide table to a long table.
At the moment it looks like this:
9 Answe...
Rails migrations: Undo default setting for a column
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Rails 5+
def change
change_column_default( :table_name, :column_name, from: nil, to: false )
end
Rails 3 and Rails 4
def up
change_column_default( :table_name, :column_name, nil )
end
def down
change_column_default( :table_name, :column_name, false )
end
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The multi-part identifier could not be bound
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FROM (a, b) LEFT JOIN dkcd ON …
WHERE …
that is, the combination of tables a and b is joined with the table dkcd. In fact, what's happening is
SELECT
…
FROM a, (b LEFT JOIN dkcd ON …)
WHERE …
that is, as you may already have understood, dkcd is joined specifically against b and onl...
Remove empty space before cells in UITableView
I am currently trying to put a UITableView in a different location rather than at the top of my view controller. With this said, it is trying to add the header in the top to account for the navigation bar, but this is not needed since I do not have at the top of my controller.
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Check if value exists in Postgres array
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how can I search for a column from another table to have a value in the array? e.g. select * from beers where style_id in (select preferences from users where id=1) limit 1; style_id is an integer data type; preferences is integer[] I get this error ERROR: operato...
How do I delete a fixed number of rows with sorting in PostgreSQL?
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You could try using the ctid:
DELETE FROM logtable
WHERE ctid IN (
SELECT ctid
FROM logtable
ORDER BY timestamp
LIMIT 10
)
The ctid is:
The physical location of the row version within its table. Note that although the ctid can be used to locate the...