Call an Oracle function from Java

Question

I am having issues calling an Oracle FUNCTION (not a Stored Procedure) from Java 1.6, using ojdbc14.jar.

I do not know what the function contains as I am calling it

Answer 1

it should be:

String call = "{ ? = call FCRLIVE.AP_CH_GET_ACCT_BALANCES(?, ?, ?, ?, ?) }";

Answer 2

You need to define parameter returned by function:

String call = "{ ? = call FCRLIVE.AP_CH_GET_ACCT_BALANCES(?, ?, ?, ?, ?) }";
                  CallableStatement cstmt = conn.prepareCall(call);
                  cstmt.setQueryTimeout(1800);
                  cstmt.registerOutParameter(1, ...Type returned by function);
                  cstmt.setString(2, inputCode);
                  cstmt.registerOutParameter(3, oracle.jdbc.OracleTypes.NUMBER);
                  cstmt.registerOutParameter(4, oracle.jdbc.OracleTypes.VARCHAR);
                  cstmt.registerOutParameter(5, oracle.jdbc.OracleTypes.CHAR);
                  cstmt.registerOutParameter(6, oracle.jdbc.OracleTypes.CHAR);
                  cstmt.executeUpdate();

Answer 3

your return parameter is only one. the first one. that's the only one you must register its type. so, first thing first:

cstmt.registerOutParameter(1, oracle.jdbc.OracleTypes.VARCHAR);

then set/register the other parameters as needed, but you have 6 parameters as in question marks and you handle only 5. you'll need to set the 6th one as well:

cstmt.setString(6, myVariable);

if it is not clear, please post the prototype of sql function you are using and I'll point you to exact missing binding.

Answer 4

There are actually multiple ways of doing so. But the easiest of them all is firing a query. Here's how to do it.

String sql="select myFunction('"+number+"','"+date"') from dual";
statement.execute(sql);

Set the input and output parameters if you are using JDBC.

If you are using hibernate use Named Queries something like this: YourMapping.hbm.xml

<sql-query name="my_function" callable="true">
<return alias="demo" class="net.bean.Demo">
<return-property name="id" column="id"/>
<return-property name="fname" column="fname"/>
<return-property name="lname" column="lname"/>
</return>
    {?=call demoFunc(:param1,:param2)}
</sql-query>

Now this will create a Named Query for the function

Next thing to do is simply call it using following code

Query query=session.getNamedQuery("my_function");
query.setParameter("parma1",date);
query.setParameter("parma2",number);
query.executeUpdate();

Note that in hbm.xml file the return class name and properties exists only apply if you have mapped the returning values if the function returning appropriate values.