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What's wrong with nullable columns in composite primary keys?
...n optionally be related to B, the clean solution is to create a resolution table (let's say AB). That table would link A with B: If there is a relationship then it would contain a record, if there isn't then it would not.
sh...
SQL Server SELECT LAST N Rows
...Feature also. A great example can be found here:
I am using the Orders table of the Northwind database... Now let us retrieve the Last 5 orders placed by Employee 5:
SELECT ORDERID, CUSTOMERID, OrderDate
FROM
(
SELECT ROW_NUMBER() OVER (PARTITION BY EmployeeID ORDER BY OrderDate DESC) AS Or...
Entity Framework Join 3 Tables
I'm trying to join three tables but I can't understand the method...
2 Answers
2
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How do I split a string so I can access item x?
...-in function STRING_SPLIT that will split a string and return a one-column table result which you can use in a SELECT statement or elsewhere.
– qJake
Apr 3 '17 at 20:24
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Declaring a default constraint when creating a table
I am creating a new table in Microsoft SQL server 2000 by writing the code instead of using the GUI, I am trying to learn how to do it "the manual way".
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UITableView - scroll to the top
In my table view I have to scroll to the top. But I cannot guarantee that the first object is going to be section 0, row 0. May be that my table view will start from section number 5.
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access denied for load data infile in MySQL
...mple, this gives the permission problem:
LOAD DATA INFILE '{$file}' INTO TABLE {$table}
Add LOCAL to your statement and the permissions issue should go away. Like so:
LOAD DATA LOCAL INFILE '{$file}' INTO TABLE {$table}
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MySql : Grant read only options?
...ns on database.
It depends on how you define "all read."
"Reading" from tables and views is the SELECT privilege. If that's what you mean by "all read" then yes:
GRANT SELECT ON *.* TO 'username'@'host_or_wildcard' IDENTIFIED BY 'password';
However, it sounds like you mean an ability to "see" ...
How to insert a SQLite record with a datetime set to 'now' in Android application?
Say, we have a table created as:
10 Answers
10
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Why would anyone use set instead of unordered_set?
... and many other places. What I understand is that unordered_set is hash table with O(1) lookup complexity. On the other hand, set is nothing but a tree with log(n) lookup complexity. Why on earth would anyone use set instead of unordered_set? i.e is there a need for set anymore?
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