PL/SQL Practice cursor cursor:oracle A private area of memory allocated for SQL statements when executing SQL statements

Implicit cursors: You can only return one row of results at a time (no definition, default auto-build)
Span style= "Font-family:courier new, Courier; FONT-SIZE:16PX ">  explicit cursor: Requires a developer to define in advance, you can loop through the SQL statements in the cursor, return multiple rows of results
 
  Properties of an implicit cursor:
   sql%rowcout     statistics The number of records processed in a cursor
   sql%found      If a record matching the criteria can be found in the cursor, the result is true
   sql%notfound   if a record that matches the condition can be found in the cursor, the result is true
   sql%isopen     determines whether a cursor is open, and the default cursor in an implicit cursor automatically opens

1. An implicit cursor:

Sql%NotFound If a record that matches a condition can not be found in the cursor, the result is true SQL> Declare  2    3v_id t1.id%type; 4    5  begin  6    7V_ID:=Ten; 8    9    UpdateT1SetId= - whereId=v_id;Ten    ifSql%NotFound Then  One    Insert  intoT1 (ID)Values(v_id); A    Commit;  -    End if;  -  End;

2. Sql%found if a record matching the criteria can be found in the cursor, the result is true

Sql> Declare  2    3v_id t1.id%type; 4    5  begin  6    7V_ID:=Ten; 8    9    Delete  fromT1whereId=v_id;Ten    One    ifSql%Found Then  ADbms_output.put_line ('T1 Recorder is delete!');  -    Commit;  -    End if;  the  End;

3.sql%rowcout statistics The number of records processed in the cursor

Sql> Declare  2    3v_id t1.id%type; 4    5  begin  6    7V_ID:=Ten; 8    9    Insert  intoT1 (ID)Values(v_id);Ten    Delete  fromT1whereId=v_id; One    A    ifSql%Found Then  -Dbms_output.put_line ('T1 Recorder is delete!');  -Dbms_output.put_line ('T1 Recorders'||Sql%RowCount||'rows was deleted!');//Count the number of deleted rows the    Commit;  -    End if;  -  End;

PL/SQL Practice cursor cursor:oracle A private area of memory allocated for SQL statements when executing SQL statements