Why named parameter can't be used multiple times in PL/SQL block in JDBC

Question

with the following PL/SQL block, when I run int in JDBC, I get an error,
it says, The number of parameter names does not match the number of registered parameters.
if all named parameters are used only once, then my program works fine.
My old program uses Oracle Forms to run the attached PL/SQL block correctly, I just want to run them in JDBC without more efforts, I don't want to rewrite all PL/SQL blocks.
Does oracle driver support this case? why the PL/SQL block can work in Oracle Forms but failed in JDBC?
Can we have an another solutions to avoid rewriting the PL/SQL block to stored procedure?
if I use following SQL:
BEGIN if :q is null then :q := 'X'; else :q := 'Y'; end if; END;
, Using java program:
import java.sql.*; public class RunPLSQLBlock { public static void main(String s[]) throws SQLException { String URL = "jdbc:oracle:thin:@192.168.11.199:1521:TIBSTEST"; Connection con = null; try { Class.forName("oracle.jdbc.driver.OracleDriver"); con = (Connection) DriverManager.getConnection(URL, "FBP1DEV", "FBP1DEV"); String SQL = "BEGIN  if :q is null then  :q := 'X'; else :q := 'Y'; end if; END;"; CallableStatement stmt = con.prepareCall(SQL); stmt.registerOutParameter("q", Types.VARCHAR); stmt.setString("q", "A"); stmt.execute(); } catch (Exception e) { e.printStackTrace(); } finally { if (con != null) { con.close(); } } } }
in the coding, only "q" registered, I got:
java.sql.SQLException: The number of parameter names does not match the number of registered praremeters at oracle.jdbc.driver.OracleSql.setNamedParameters(OracleSql.java:314) at oracle.jdbc.driver.OracleCallableStatement.execute(OracleCallableStatement.java:10096) at oracle.jdbc.driver.OraclePreparedStatementWrapper.execute(OraclePreparedStatementWrapper.java:5693) at RunPLSQLBlock.main(RunPLSQLBlock.java:28)
now, tried to register 3 indexes, changed fragments are below.
import java.sql.*; public class RunPLSQLBlock { public static void main(String s[]) throws SQLException { String URL = "jdbc:oracle:thin:@192.168.11.199:1521:TIBSTEST"; Connection con = null; try { Class.forName("oracle.jdbc.driver.OracleDriver"); con = (Connection) DriverManager.getConnection(URL, "FBP1DEV", "FBP1DEV"); String SQL = "BEGIN  if :q is null then  :q := 'X'; else :q := 'Y'; end if; END;"; CallableStatement stmt = con.prepareCall(SQL); stmt.registerOutParameter(1, Types.VARCHAR); stmt.registerOutParameter(2, Types.VARCHAR); stmt.registerOutParameter(3, Types.VARCHAR); stmt.setString(1, "A"); stmt.execute(); } catch (Exception e) { e.printStackTrace(); } finally { if (con != null) { con.close(); } } } }
now error changed to:
java.sql.SQLException: ORA-01006: bind variable does not exist at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:457) at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:400) at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:926) at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:476) at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:200) at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:543) at oracle.jdbc.driver.T4CCallableStatement.doOall8(T4CCallableStatement.java:208) at oracle.jdbc.driver.T4CCallableStatement.executeForRows(T4CCallableStatement.java:1416) at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1757) at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:4372) at oracle.jdbc.driver.OraclePreparedStatement.execute(OraclePreparedStatement.java:4595) at oracle.jdbc.driver.OracleCallableStatement.execute(OracleCallableStatement.java:10100) at oracle.jdbc.driver.OraclePreparedStatementWrapper.execute(OraclePreparedStatementWrapper.java:5693) at RunPLSQLBlock.main(RunPLSQLBlock.java:26)
, now tried register only 1 position like below,
  CallableStatement stmt = con.prepareCall(SQL);   stmt.registerOutParameter(1, Types.VARCHAR);   stmt.setString(1, "A");   stmt.execute();
, it says:
java.sql.SQLException: Missing IN or OUT parameter at index:: 2 at oracle.jdbc.driver.OraclePreparedStatement.processCompletedBindRow(OraclePreparedStatement.java:2177) at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:4356) at oracle.jdbc.driver.OraclePreparedStatement.execute(OraclePreparedStatement.java:4595) at oracle.jdbc.driver.OracleCallableStatement.execute(OracleCallableStatement.java:10100) at oracle.jdbc.driver.OraclePreparedStatementWrapper.execute(OraclePreparedStatementWrapper.java:5693) at RunPLSQLBlock.main(RunPLSQLBlock.java:26)
, now let try a OK case, which use all named parameters only once. coding like below, SQL and Java listed below.
BEGIN if :q is null then :r := 'X'; else :s := 'Y'; end if; EXCEPTION   WHEN NO_DATA_FOUND THEN     NULL; END;
import java.sql.*; public class RunPLSQLBlock { public static void main(String s[]) throws SQLException { String URL = "jdbc:oracle:thin:@192.168.11.199:1521:TIBSTEST"; Connection con = null; try { Class.forName("oracle.jdbc.driver.OracleDriver"); con = (Connection) DriverManager.getConnection(URL, "FBP1DEV", "FBP1DEV"); String SQL = "BEGIN  if :q is null then  :r := 'X'; else :s := 'Y'; end if; END;"; CallableStatement stmt = con.prepareCall(SQL); stmt.registerOutParameter("q", Types.VARCHAR); stmt.registerOutParameter("r", Types.VARCHAR); stmt.registerOutParameter("s", Types.VARCHAR); stmt.setString("q", "A"); stmt.execute(); System.out.println("Q :" + stmt.getString("q")); System.out.println("R :" + stmt.getString("r")); System.out.println("S :" + stmt.getString("s")); } catch (Exception e) { e.printStackTrace(); } finally { if (con != null) { con.close(); } } } }
, the case give us the following output:
Q :A R :null S :Y
2nd part, I also tried another scheme, to use 'execute immediate', test code attached below, it also have errors.
begin execute immediate 'begin if :q is null then :q := ''X''; else :q := ''Y''; :r := ''Z''; end if; end;' using in out :q, out :r; end;
, Java Code:
import java.sql.*; public class RunDynamicSQL { public static void main(String s[]) throws SQLException { String URL = "jdbc:oracle:thin:@192.168.11.199:1521:TIBSTEST"; Connection con = null; try { Class.forName("oracle.jdbc.driver.OracleDriver"); con = (Connection) DriverManager.getConnection(URL, "FBP1DEV", "FBP1DEV"); String SQL ="begin execute immediate 'begin if :q is null then :q := ''X''; else :q := ''Y''; :r := ''Z''; end if; end;' using in out :q, out :r; end;"; CallableStatement stmt = con.prepareCall(SQL); stmt.registerOutParameter("q", Types.VARCHAR); stmt.registerOutParameter("r", Types.VARCHAR); stmt.setString("q", "A"); stmt.execute(); System.out.println("Q :" + stmt.getString("q")); System.out.println("R :" + stmt.getString("r")); } catch (Exception e) { e.printStackTrace(); } finally { if (con != null) { con.close(); } } } }
, the output is, we can find when parameter 'q' is IN OUT mode, we can't get its final value:
Q :null R :Z
, now I tried my workaround, it works fine by using a temporary variable, now my named parameter is split to 2 roles, one is for IN, another is for OUT, now I can get final out value.
declare q clob; r clob; begin q := ?; r := ?; execute immediate 'begin if :q is null then :q := ''X''; else :q := ''Y''; :r := ''Z''; end if; end;' using in out q, out r; ? := q; ? := r; end;
, my test java code,
import java.sql.*; public class RunDynamicSQL { public static void main(String s[]) throws SQLException { String URL = "jdbc:oracle:thin:@192.168.11.199:1521:TIBSTEST"; Connection con = null; try { Class.forName("oracle.jdbc.driver.OracleDriver"); con = (Connection) DriverManager.getConnection(URL, "FBP1DEV", "FBP1DEV"); String SQL ="declare q clob;r clob; begin q := ?; r := ?; execute immediate 'begin if :q is null then :q := ''X''; else :q := ''Y''; :r := ''Z''; end if; end;' using in out q, out r; ? := q; ? := r; end;"; CallableStatement stmt = con.prepareCall(SQL); stmt.registerOutParameter(3, Types.VARCHAR); stmt.registerOutParameter(4, Types.VARCHAR); stmt.setString(1, "A"); stmt.setString(2, "A"); stmt.execute(); System.out.println("Q :" + stmt.getString(3)); System.out.println("R :" + stmt.getString(4)); } catch (Exception e) { e.printStackTrace(); } finally { if (con != null) { con.close(); } } } }
, the output is expected,
Q :Y R :Z
Database:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
JDBC Driver, extracted from ojdbc6_g.jar/META-INF/MANIFEST.MF :
Created-By: 1.5.0_30-b03 (Sun Microsystems Inc.)
Implementation-Vendor: Oracle Corporation
Implementation-Title: JDBC debug
Implementation-Version: 11.2.0.3.0
Repository-Id: JAVAVM_11.2.0.3.0_LINUX_110823
Specification-Vendor: Sun Microsystems Inc.
Specification-Title: JDBC
Specification-Version: 4.0
Main-Class: oracle.jdbc.OracleDriver
JDK:
java version "1.7.0"
Java(TM) SE Runtime Environment (build 1.7.0-b147)
Java HotSpot(TM) Client VM (build 21.0-b17, mixed mode, sharing)
Edited by: jamxval on 2013-3-22 2:01PM (UTC+08:00), Give full test java program and SQL, added environment/API level; Attached another problem.
Edited by: jamxval on 2013-3-26 17:57 (UTC +08), Adjust code style

Answer 1

Hi, thanks for your response, now I see, the named parameter is for stored procedure only, for PL/SQL block we name it placeholder name.
After cast my java.sql.CallableStatement to oracle.jdbc.OracleCallableStatement, I can find setStringAtName,
now, I have only one question:I can't find corresponding methods for registerOutputParameter, how we fetch output value?
I tried to callableStatement.getString("q"); it reports errors, but there are no ordinal binding in my source code, does placeholder names doesn't support OUT mode?
Java:
CallableStatement stmt = con.prepareCall("BEGIN  if :q is null then  :r := 'X'; else :s := 'Y'; end if; END;");
oracle.jdbc.OracleCallableStatement call = (oracle.jdbc.OracleCallableStatement) stmt;
call.registerOutParameter("q", Types.VARCHAR);
call.registerOutParameter("r", Types.VARCHAR);
call.registerOutParameter("s", Types.VARCHAR);
call.setStringAtName("q", "A");
call.setStringAtName("r", "A");
call.setStringAtName("s", "A");
call.execute();
System.out.println("Q :" + call.getString("q"));
</Java>
<output>
java.sql.SQLException: 不允许的操作: Ordinal binding and Named binding cannot be combined!
     at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
     at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:146)
     at oracle.jdbc.driver.OracleCallableStatement.getString(OracleCallableStatement.java:2834)
     at RunPLSQLBlock.main(RunPLSQLBlock.java:33)
</output>by the way, in my below-mentioned SQL 'problematic', when my code uses 'execute immediate' and use placeholder names in IN OUT mode, we always get NULL value (i.e. ':q'), but we can get final value of ':r' when ':r' is OUT mode only; now I get a workaround attached in below-mentioned 'my workaround' block, which split the IN OUT roles to 2 parts, it can work now;
It seems that the difference between 'problematic' and 'my workaround' imply that there are something work unexpectedly when the driver process the placeholder names, because 'my workaround' and ':r in problematic case' make sure the 'execute immediate' returned output values correctly, unluckly driver layer can't get return values.
<SQL name = 'problematic'>
begin
     execute immediate 'begin if :q is null then :q := ''X''; else :q := ''Y''; :r := ''Z''; end if; end;'
     using in out :q, out :r;
end;
</SQL>
<SQL name='my workaround'>
declare     
     q clob;
     r clob;
begin
     q := ?;
     r := ?;
     execute immediate 'begin if :q is null then :q := ''X''; else :q := ''Y''; :r := ''Z''; end if; end;' using in out q, out r;
     ? := q;
     ? := r;
end;Edited by: EJP on 26/03/2013 14:14