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Database query result producing null values  RSS feed

 
Greenhorn
Posts: 26
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so this is my code it compiles and runs but it does not produce the correct output. any idea why??
 
Rancher
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15
Java Notepad
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In case the getUserID() method (looks like it is doing that) is to insert into two tables UserStocks and Stocks there should be two executeUpdate statements. Nested try-catch blocks are not necessary.

All the JDBC code including executeUpdate need to be in try-catch blocks. Also, each PreparedStatement should be closed after its execution. The method name getUserID() can be changed to a more appropriate name like insertStocks().

Oracle's Java JDBC tutorials have good examples of how the API is used.

EDIT: It looks like you are not capturing the stock symbol (its value will be null in the database tables) in the posted code.
 
Saloon Keeper
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it does not produce the correct output


What output did you expect, and what output did you get?


           catch(Exception e)
           {
           }


An empty catch block is rarely a good idea - at the very least log any exceptions to where you will see them. Otherwise, how will you know what problems there are?
 
Yogi Permaul
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The output i'm getting is null when running the application.
The output is supposed to be of the stocks from the database
 
Tim Moores
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Then you need to delve a little deeper into the code - which print statement prints that "null"?

Be aware that line 27 prints out two variables that haven't been initialized, so if those are null, that's to be expected. I also note that the getUserID method does nothing of the sort - it retrieves no data from the DB. That looks wrong.
 
Consider Paul's rocket mass heater.
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