Can somebody explain dbms_sql.number_table [closed] - plsql

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I tried to search this but could not get a satisfactory answer hence posting here . somebody please explain

Answer 1

Better to understand DBMS_SQL itself to some extent, before understanding NUMBER_TABLE.
( I do this for My Learning!)
NUMBER_TABLE
is Actually,
TYPE number_table IS TABLE OF NUMBER INDEX BY BINARY_INTEGER;
So, only numbers are allowed!
FlowChart on How DBMS_SQL Works! :
Your interested area comes in bind variable box
-- | open_cursor |
-- -----------
-- |
-- |
-- v
-- -----
-- ------------>| parse |
-- | -----
-- | |
-- | | ---------
-- | v |
-- | -------------- |
-- |-------->| bind_variable | |
-- | ^ ------------- |
-- | | | |
-- | -----------| |
-- | |<--------
-- | v
-- | query?---------- yes ---------
-- | | |
-- | no |
-- | | |
-- | v v
-- | ------- -------------
-- |----------->| execute | ->| define_column |
-- | ------- | -------------
-- | |------------ | |
-- | | | ----------|
-- | v | v
-- | -------------- | -------
-- | ->| variable_value | | ------>| execute |
-- | | -------------- | | -------
-- | | | | | |
-- | ----------| | | |
-- | | | | v
-- | | | | ----------
-- | |<----------- |----->| fetch_rows |
-- | | | ----------
-- | | | |
-- | | | v
-- | | | -----------------
-- | | | | column_value |
-- | | | | variable_value |
-- | | | -----------------
-- | | | |
-- | |<--------------------------
-- | |
-- -----------------|
-- |
-- v
-- ------------
-- | close_cursor |
--
------------
Example:
In a DELETE statement, for example, you could bind in an array in the WHERE clause and have the statement be run for each element in the array:
DECLARE
stmt VARCHAR2(200);
dept_no_array DBMS_SQL.NUMBER_TABLE;
c NUMBER;
dummy NUMBER;
begin
dept_no_array(1) := 10; dept_no_array(2) := 20; /* Put some values into the array */
dept_no_array(3) := 30; dept_no_array(4) := 40;
dept_no_array(5) := 30; dept_no_array(6) := 40;
stmt := 'delete from emp where deptno = :dept_array'; /* A Dynamic SQL String with a bind variable */
c := DBMS_SQL.OPEN_CURSOR; /* Open a Cursor! */
DBMS_SQL.PARSE(c, stmt, DBMS_SQL.NATIVE); /* Parse the Dynamic SQL , making it happen on the native database to which is connected! */
DBMS_SQL.BIND_ARRAY(c, ':dept_array', dept_no_array, 1, 4);
/* Bind only elements 1 through 4 to the cursor Happens 4 times */
dummy := DBMS_SQL.EXECUTE(c);
/* Execute the Query, and return number of rows deleted! */
DBMS_SQL.CLOSE_CURSOR(c);
EXCEPTION WHEN OTHERS THEN
IF DBMS_SQL.IS_OPEN(c) THEN
DBMS_SQL.CLOSE_CURSOR(c);
END IF;
RAISE;
END;
/
P.S. Pure rip-off, with some more commments ,from Oracle