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PL/SQL NDS Reference Cursor with Record Collection

without comments

Somebody got to this blog looking for a way to write a Native Dynamic SQL (NDS) statement that returned a system reference cursor. I created an image file to show how to do that. I borrowed the code from Chapter 11 of Oracle Database 11g PL/SQL Programming. The only problem with this is that it’s a PL/SQL only solution typically. You can write it as a function or procedure, and then use a Java or PHP program to display the reference cursor in a web page. You can check this previous post for a PHP example.

 Native Dynamic SQL Reference Cursor

Written by maclochlainn

May 31st, 2008 at 8:19 pm

Entering a colon in an NDS statement

with 2 comments

Somebody asked me how you include a colon in a Native Dynamic SQL (NDS) statement when it’s not related to a placeholder. A colon without a placeholder raises an ORA-00947 error when parsing the statement. The error means you’ve failed to submit enough bind variables. You can substitute a CHR(58) where you need to insert the standalone colon. The NDS or DBMS_SQL parsing phase ignores a CHR(58), which translates during actual SQL statement parsing as a colon.

Let’s say you want to insert a column value with an ASIN (Amazon Standard Identification Number) code in the format: ASIN: B000VBJEEG

Using NDS, you have two choices. You can let the entry person type the full string and pass that string as a bind variable, or you can substitute CHR(58) for the colon and enter only the ASIN code. The example (Oracle Database 11g PL/SQL Programming, pp. 386-387) implements the latter:

CREATE OR REPLACE PROCEDURE insert_item
( asin VARCHAR2
, item_type VARCHAR2
, item_title VARCHAR2
, item_subtitle VARCHAR2 := ''
, rating VARCHAR2
, agency VARCHAR2
, release_date DATE ) IS
 
  -- Local variable for a dynamic SQL statement.
  stmt VARCHAR2(2000);
 
BEGIN
 
  -- Create a dynamic statement with bind variables.
  stmt := 'INSERT INTO item '
  || '( item_id'
  || ', item_barcode'
  || ', item_type'
  || ', item_title'
  || ', item_subtitle'
  || ', item_desc'
  || ', item_blob'
  || ', item_photo'
  || ', item_rating'
  || ', item_rating_agency'
  || ', item_release_date' 
  || ', created_by'
  || ', creation_date'
  || ', last_updated_by'
  || ', last_update_date ) '
  || 'VALUES '
  || '( item_s1.nextval'
  || ',''ASIN''||CHR(58)||:asin'
  || ',(SELECT common_lookup_id'
  || ' FROM common_lookup'
  || ' WHERE common_lookup_type = :item_type)'
  || ', :item_title'
  || ', :item_subtitle'
  || ', empty_clob()'
  || ', NULL, NULL'
  || ', :rating'
  || ', :agency'
  || ', :release_date'
  || ', 3, SYSDATE, 3, SYSDATE)';
 
  -- Print debug statement.
  dbms_output.put_line(stmt);
 
  -- Execute dynamic statement with bind variables.
  EXECUTE IMMEDIATE stmt
  USING asin, item_type, item_title, item_subtitle, rating, agency, release_date;
END insert_item;
/

There’s quite a nifty or nasty trick inside the dynamic SQL statement. You’ll notice that the colon is concatenated to the ASIN and a bind variable. It is critical that you don’t encapsulate the bind variable inside quotes, or you’ll raise an ORA-01006 exception (check Table 11-2 in the Oracle Database 11g PL/SQL Programming book for more detail). You can’t enclose a string in single quotes because the string is substituted as a string, and it trips up the parser.

You can test this dynamic SQL statement with the following anonymous PL/SQL block:

BEGIN
  insert_item('B00005JPO1'
             ,'DVD_WIDE_SCREEN'
             ,'Indiana Jones and the Crystal Skull'
             ,'2-Disc Special Edition'
             ,'PG-13'
             ,'MPAA'
             ,'14-OCT-08');
END;
/

Written by maclochlainn

May 10th, 2008 at 4:58 am