well, I am wondering which statement to call on CallableStatement in order to call stored procedure with both insert and select operations, execute()/excecuteUpdate()/executeQuery(),
I'm sorta confused which one to use ? after I must do the both operations, do I have to separate the 2 operations by creating stored procedure a piece ? thank you .
For select use ExecuteQuery()
For the rest of the crud elements use ExecuteNonquery()
Related
I am wondering if it is possible to call a stored procedure (from .net vb) and send it one value. The stored procedure will take that value, execute a select statement, then reuse the 3-5 selected values and execute another select statement. I am trying to keep it all within one stored procedure.
I have written a stored procedure that includes a SELECT on a number of tables that applies logic to calculate values and transforms some of the data.
I have been asked if I can exclude records from the resultset in the stored procedure and write the record to a separate log table. I was looking to loop through the result set from the SELECT statement and delete the record I want to exclude once I have written it to a table. At the moment I am struggling to find the syntax to delete from the result set of a SELECT statement in a stored procedure and can only find how to use the cursor reference to delete from the original database table.
I need to remove the records in the same stored procedure and I am looking to avoid duplicating the logic by using some of the logic to find the records to include and repeat some of the logic again to be able to find the records to exclude. The only other alternative I can think of is using a temporary table, but I think what I am trying to do should be possible.
Any help appreciated.
When you have an open cursor in a stored procedure (or in an application), you can perform positioned deletes. You can execute the statement,
DELETE WHERE CURRENT OF cursorname;
Please be aware that by default issuing a COMMIT statement will close any open cursors, so if you plan to have this delete operation spread over multiple transactions you will need to declare your cursors using WITH HOLD.
I am using Delphi2010 and I'm trying to do an insert into multiple tables. I don't know the best way to do this. What I'm wondering is if there is a possible way to do one insert using one of Delphi's tools like the TQuery or TClientDataSet or would it be better to use code (we use Pascal language). An array maybe? I haven't been using Delphi that long but I have inserted and updated info into one table before, not multiple. Also, these tables use pretty much the same field names.
Any help would be greatly appreciated.
Thanks in advance!!
Call a stored procedure to update your tables simultaneously, with a transaction wrapper. Or re-design your database to eliminate duplicate/redundant data, so that you would never need to update several tables at once.
Note that this answer is perfectly valid, given the information provided in the question...
(Note: it's late, couldn't sleep, bored. This is what you get, given the quality of the information in the question!)
Another possible solution could be to make a updateable view on the database, and update the view from Delphi.
Making a updateable view just moves the work of updating 2 tables to the SQL instead of in Delphi.
This moves the business logic to the sql instead of in the Delphi. It propobly also generates less network trafic.
As Chris writes: use transactions, when 2 or more updates/inserts is dependent of each other.
Which data access componentes do you use ?
Which restrictions do you have ?
do you want to insert the same values into both tables ?
why not easy like:
for i = low(tables) to high(tables) do
begin
query.sql.text := 'insert into '+tables[i]+' (fields) values('+ ...)';
query.execsql;
end;
I thought I would use a stored routine to clean up some of my more complex SQL statements. From what I've read, it seems impossible to use a stored procedure within an sql statement, and a stored function only returns a single value when what I need is a result set. I am using mySQL v5.0
SELECT p.`id`, gi.`id`
FROM `sport`.`players` AS p JOIN `sport`.`gameinstances` AS gi
ON p.`id` = gi.`playerid`
WHERE (p.`playerid` IN (CALL findPlayers`("Canada", "2002")))
AND (gi.`instanceid` NOT IN (CALL findGameInstances`("Canada", "2002")));
For example, the procedures 'findPlayers' and 'findGameInstances' are are stored routines that execute some SQL and return a result set. I would prefer not to include their code directly within the statement above.
I don't know if mysql can use any of these techniques, but in SQl server I would try one of two different things (at least it might give you something to look for in th emysql documentation):
First a table values used defined function then join to that
Second, insert the results set of the sp into a temp table then join to the tem table
You could also consider putting the complicated logic in a view and then just adding the where clause after joining to the view. This won't work if your stored proc does dynamic things a view can't do, but it is a possibilty.
I am attemting to create a storedproc that reads like:
Select
ep.EmployeeID, GetEmployeeFirstName(ep.EmployeeID),
GetEmployeeLastName(ep.EmployeeID), ed.EmployeeDateOfBirth,
ed.EmployeeAddress, ed.EmployeeAddress2, ed.City, ed.State, ed.ZipCode
From
EmployeeProfile ep, EmployeeDetail ed
Where
ep.EmployeeID = ed.EmployeeID
This block of code will be a stored procedure.
My issue is that GetEmployeeFirstName is a stored proc that has to be passed an EmployeeID to get the employees first and last name.
How can I call a storedproc within a stored proc.
Thanks
Mike
These would probably be better suited as a function.
GetEmployeeFirstName(ep.EmployeeID), GetEmployeeLastName(ep.EmployeeID)
Better yet, just join the table that has the names.
I don't understand what these stored procedures do. Even if the first and last name are not in the EmployeeProfile table, and even if you have to do some manipulation of the strings before they are returned, a join would be a much better solution than a stored procedure or function. Especially when you take performance into account.
If you have the GetEmployeexName sprocs because you use them elsewhere, that's fine. Whatever they do, I would not consider it code duplication if they don't get called from your query.
You need to understand that for every row in your result set, two other procedures or functions get called. This is extremly costly and can render an application unacceptably slow, even for relatively small result sets of a few thousand employees. I know what I am talking about - I removed a lot of function calls from queries during a recent database tuning initiative.
In SQL Server, in order to call the GetEmployeeLastName within the Select statement list I would convert it to a database Function.
You can use EXEC or sp_executesql to execute a stored procedure from another stored procedure. (BTW, you have not specified your RDBMS).
Doesn't your table EmployeeDetail contain the employee's first and last name?
Select
ep.EmployeeID, ed.FirstName
ed.LastName, ed.EmployeeDateOfBirth,
ed.EmployeeAddress, ed.EmployeeAddress2,
ed.City, ed.State, ed.ZipCode
From
EmployeeProfile ep
inner join EmployeeDetail ed ON ep.EmployeeID = ed.EmployeeID