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What is causing ERROR: there is no unique constraint matching given keys for referenced table?
Below example table structure gives an ERROR: there is no unique constraint matching given keys for referenced table, and having stared at it for while now I can't figure out why this error arises in this situation.
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Querying data by joining two tables in two database on different servers
There are two tables in two different databases on different servers, I need to join them so as to make few queries. What options do I have? What should I do?
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Are soft deletes a good idea? [duplicate]
...ow have to include a WHERE IsDeleted = false clause in every query on this table (and so much worse if you're JOINing these tables). A mistake here would be caught as soon as a user or tester noticed a deleted record showing up again, which might take some time. Also, it would be easy for a develo...
Adding a new value to an existing ENUM Type
I have a table column that uses an enum type. I wish to update that enum type to have an additional possible value. I don't want to delete any existing values, just add the new value. What is the simplest way to do this?
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
As the title says, I am trying to insert into one table selecting values from another table and some default values.
5 Ans...
Eliminate extra separators below UITableView
When I set up a table view with 4 rows, there are still extra separators lines (or extra blank cells) below the filled rows.
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How do I make a composite key with SQL Server Management Studio?
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Open the design table tab
Highlight your two INT fields (Ctrl/Shift+click on the grey blocks in the very first column)
Right click -> Set primary key
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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...OUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those rare cases is equivalent to count(*)
Use count(*) for counting
U...
Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
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You have a mismatch of two different collations in your table. You can check what collations each column in your table(s) has by using this query:
SELECT
col.name, col.collation_name
FROM
sys.columns col
WHERE
object_id = OBJECT_ID('YourTableName')
Collations are n...
What is the simplest SQL Query to find the second largest value?
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SELECT MAX( col )
FROM table
WHERE col < ( SELECT MAX( col )
FROM table )
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