![]() Does anybody know how can I do such a thing? The expected result is this. Something like this: CALL u.id, 'WEEK') īut it throws syntax error. I don't want to pass it manually by hand. But please focus on the third parameter which is 10. Ok, I can call procedure about like this: CALL 10, 'WEEK') So I have to pass those two which have IN direction when I call the procedure. Both vote_value and score have OUT direction (as result), And both user_id and time_range have IN Direction. THEN unix_timestamp(DATE_SUB(now(), INTERVAL 1 YEAR))Īs you see my procedure has 4 parameters. THEN unix_timestamp(DATE_SUB(now(), INTERVAL 1 MONTH)) THEN unix_timestamp(DATE_SUB(now(), INTERVAL 1 WEEK)) SELECT coalesce(sum(vote_value), 0), coalesce(sum(score), 0) So here we created a cursor which fetch all cities and then creates and executed all select statements at runtime for all cities.I have this stored procedure: CREATE PROCEDURE `test`(OUT `vote_value` INT, OUT `score` INT, IN `user_id` INT, IN `time_range` INT) We want to proceed the select query for displaying all cities but one at a time, means we want to select one city at a time but all city from a countryTable. The cursor declaration and processing is also in the BEGIN-END block. It allows iterating on the values return from the query within cursor.Ĭursor also needs to declare a variable having type CURSOR including the query from where to select data to iterate. So the declaration of handler as:ĭECLARE CONTINUE HANDLER FOR 1062 SELECT 'Error- duplicate key Found’ ĭECLARE EXIT HANDLER FOR 1062 SELECT 'Error- duplicate key Found‘ ĭeclare handler according to sql exceptions:ĭECLARE CONTINUE HANDLER FOR SQLEXCEPTION SET hasError = 1 Cursors in Stored ProcedureĬursor gives a way to create a run time loop based on the result of the query. Handler action means whether to continue the execution or exit the execution process when specified error occurs defined in the declaration of error handler.įor example, suppose we may get an error of duplicate key in the insertion query within a stored procedure so we can handle it through error handling on error number 1062 and decide whether to continue or exit the execution process. It needs to declare the handler with its action like variable declaration. So it look like this: CREATE DEFINERroot PROCEDURE postcontent (IN postName varchar (255), IN contentEn longtext, IN contentAR longtext CHARSET utf8, IN contentKU longtext CHARSET utf8). Stored procedure has very nice way to handle an error during the execution. Now the stored procedure to get the population, year data from this table by passing the country name and year as:ĭROP procedure if exists ProcedureName Error handling in stored procedure We have a table having the data of population, year for some countries as: At initial stage it takes input from the user through this variable and after execution returns the modified value to the same variable.Įxample of stored procedure showing usage of parameters: INOUT– This parameter works for both input and output parameter. It has no value in the beginning but stored procedure gives the value through this variable at the end. OUT–This is used to give the result back to the user after execution. Its value manipulates during the execution and retains afterthat. We can pass any value when we make a call to the procedure. IN – The default parameter type is IN, it denotes the input value to the stored procedure. There are three kind of parameters in MySQL stored procedures: MySQL procedures provide even more flexible way of its usage by allowing a user to pass the parameters and also give back the output through parameters. Here the country fetching from the table and assign to variable name COUNTRY having the scope of stored procedure only. CREATE PROCEDURE GETDT ( in startDate DATETIME, in endDate DATETIME ) BEGIN if startDate is null or endDate is null then SELECT FROM test else SELECT FROM test WHERE test.sdate > startDate AND test.edate < endDate end if END. SELECT DISTINCT(COUNTRY) from tableName where Capital=’Delhi’ INTO COUNTRY Statement to determine what your Stored Procedure will select. Or you can also assign the value using INTO keyword with select statement, for example as: To assign a value to a variable, we have to use a SET keyword, for example to set a value to variable COUNTRY the simple syntax is: Syntax of declaring a variable within stored procedure is:ĭECLARE variableNamedataType(size) DEFAULT defaultValue ĭECLARE COUNRTY VARCHAR(100) Default ‘United States’ Declaring a variable need DECLARE keyword, its name, its data types, range and default value if any. These variables are local to a stored procedure mean within the BEGIN END block, if you want to make it session variable and available to a user during its session then use in the variable name beginning. Like any programming we can use variables for calculations within the BEGIN END block of stored procedure. CALL procedureName () Variables in Stored Procedure
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