![]() The select statement runs the function hello(5) for each row returned by yar. You created a table called yar and added three rows to it. The parameter is ignored and returns a CHAR(50) containing the value 'foobar'. You created a function called hello which takes one parameter. Verbalize and internalize what just happened: Select all the values from yar, run our function hello each time: mysql> select id, hello(5) from yar Insert three values into the table yar mysql> insert into yar values(5), (7), (9) Query OK, 0 rows affected, 1 warning (0.00 sec)Ĭreate the function mysql> create function hello(id INT)Ĭreate a simple table to test it out with mysql> create table yar (id INT) I use the view because in it it's easy to filter data and to use it explicitly in the jQuery grid, automatically order, limit number of records and so on.īut it's just an ugly workaround.Open the mysql terminal: mysql -u root -pthepassword yourdbĭrop the function if it already exists mysql> drop function if exists myfunc SELECT GroupTime, FeatureId, UserHostId, MultiplicitySum FROM MergedDenials WHERE UserHostId IN (1, 2) AND FeatureId IN (3, 4) Then to show denials from user 1 and 2 on features 3 and 4 merged every 5 seconds all you have to do is: SET := 5 So we create the view which gives us back counts for each user and can simply query from that table restricting by userid. GROUP BY GroupTime, FeatureId, UserHostId GROUP BY First.DateTime, First.FeatureId, First.UserHostId, First.Licenses ![]() SUM(Second.Multiplicity) AS MultiplicitySumĪND First.DateTime - Second.DateTime < GetDenialMergingTime() SELECT MIN(Second.DateTime) AS GroupTime, I solved the problem in the following way: CREATE FUNCTION GetDenialMergingTime() Here, a view named uscustomers is created from the customers table. If you have any frequently used complex query, you can create a view based on it so that you can reference to the view by. For example, CREATE VIEW uscustomers AS SELECT customerid, firstname FROM Customers WHERE Country 'USA' Run Code. We can assume, that spaces between real denials are much bigger than between duplications. We can create views in SQL by using the CREATE VIEW command. if we have denials (for user 1 on feature 1) in timestamps: 1,2,24,26,27,45 and user wants to group denials that are closer to each other than 4 sec, he should get something like this: 1 (x2), 24 (x3), 45 (x1). So we want to group the denials in report allowing the user to specify the timespan in which denials should be grouped. If we'd have one more resource, to fulfill this request, the next two denials would not happen. So usually, when the same user gets denial 3 times on the same feature in a couple seconds it is actually one denial. I want to display a list of denials, but sometimes, when the application gets denied, it retries a couple times just to make sure. UNIQUE INDEX DenialIndex (FeatureId, DateTime, UserHostId)Ī multiplicity is a number of identical requests recorded in the same second. Multiplicity MEDIUMINT UNSIGNED NOT NULL DEFAULT 1, I have a table storing information about the denied request: CREATE TABLE Denial Is there a solution, that I could use like this: SELECT Column FROM MyView(2) WHERE (.) SELECT Column FROM Table WHERE Value = GetMyVariable() īut it looks really crappy, and the usage is also crappy - I have to set the before each usage of the view. I found an ugly workaround: CREATE FUNCTION GetMyVariable() RETURNS INTEGER DETERMINISTIC NO SQLĪnd then the view is: CREATE VIEW MyView AS SELECT Column FROM Table WHERE Value = MySQL doesn't allow this. I'd like to make it more generic, it means to change 2 into a variable. SELECT Column FROM Table WHERE Value = 2 ![]() ![]() I have a view like this: CREATE VIEW MyView AS
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