本章內容：

1. EXECUTE IMMEDIATE語句

2. OPEN-FOR、FETCH和CLOSE語句

程式碼如下：

2. OPEN-FOR、FETCH和CLOSE語句

SQL> DECLARE
  2     TYPE zip_cur_type IS REF CURSOR;
  3     zip_cur zip_cur_type;
  4     sql_stmt VARCHAR2(500);
  5     v_zip VARCHAR2(5);
  6     v_total NUMBER;
  7     v_count NUMBER;
  8  BEGIN
  9     sql_stmt := 'SELECT zip, COUNT(*) total'||
 10                 '  FROM student '           ||
 11                 'GROUP BY zip';
 12
 13     v_count := 0;
 14     OPEN zip_cur FOR sql_stmt;
 15     LOOP
 16        FETCH zip_cur INTO v_zip, v_total;
 17        EXIT WHEN zip_cur%NOTFOUND;
 18
 19        -- Limit the number of lines printed on the
 20        -- screen to 10
 21        v_count := v_count + 1;
 22        IF v_count <= 10 THEN
 23           DBMS_OUTPUT.PUT_LINE ('Zip code: '||v_zip||
 24                                 ' Total: '||v_total);
 25        END IF;
 26     END LOOP;
 27     CLOSE zip_cur;
 28
 29  EXCEPTION
 30     WHEN OTHERS THEN
 31        IF zip_cur%ISOPEN THEN
 32           CLOSE zip_cur;
 33        END IF;
 34
 35        DBMS_OUTPUT.PUT_LINE ('ERROR: '||   SUBSTR(SQLERRM, 1, 200));
 36  END;
 37  /
Zip code: 01247 Total: 1
Zip code: 02124 Total: 1
Zip code: 02155 Total: 1
Zip code: 02189 Total: 5
Zip code: 02563 Total: 1
Zip code: 06483 Total: 1
Zip code: 06605 Total: 1
Zip code: 06798 Total: 1
Zip code: 06820 Total: 3
Zip code: 06830 Total: 3
 

SQL> DECLARE
  2     TYPE zip_cur_type IS REF CURSOR;
  3     zip_cur zip_cur_type;
  4
  5
  6     v_table_name VARCHAR2(20) := '&sv_table_name';
  7     sql_stmt VARCHAR2(500);
  8     v_zip VARCHAR2(5);
  9     v_total NUMBER;
 10
 11     v_count NUMBER;
 12  BEGIN
 13     DBMS_OUTPUT.PUT_LINE ('Totals from '||v_table_name||
 14                           ' table');
 15
 16     sql_stmt := 'SELECT zip, COUNT(*) total'||
 17                 '  FROM '||v_table_name||' '||
 18                 'GROUP BY zip';
 19
 20     v_count := 0;
 21     OPEN zip_cur FOR sql_stmt;
 22     LOOP
 23        FETCH zip_cur INTO v_zip, v_total;
 24        EXIT WHEN zip_cur%NOTFOUND;
 25
 26        -- Limit the number of lines printed on the
 27        -- screen to 10
 28        v_count := v_count + 1;
 29        IF v_count <= 10 THEN
 30           DBMS_OUTPUT.PUT_LINE ('Zip code: '||v_zip||
 31                                 ' Total: '||v_total);
 32        END IF;
 33     END LOOP;
 34     CLOSE zip_cur;
 35
 36  EXCEPTION
 37     WHEN OTHERS THEN
 38        IF zip_cur%ISOPEN THEN
 39           CLOSE zip_cur;
 40        END IF;
 41
 42        DBMS_OUTPUT.PUT_LINE ('ERROR: '||   SUBSTR(SQLERRM, 1, 200));
 43  END;
 44
 45  /
Enter value for sv_table_name: student
old   6:    v_table_name VARCHAR2(20) := '&sv_table_name';
new   6:    v_table_name VARCHAR2(20) := 'student';
Totals from student table
Zip code: 01247 Total: 1
Zip code: 02124 Total: 1
Zip code: 02155 Total: 1
Zip code: 02189 Total: 5
Zip code: 02563 Total: 1
Zip code: 06483 Total: 1
Zip code: 06605 Total: 1
Zip code: 06798 Total: 1
Zip code: 06820 Total: 3
Zip code: 06830 Total: 3
 

SQL> DECLARE
  2     TYPE zip_cur_type IS REF CURSOR;
  3     zip_cur zip_cur_type;
  4
  5     TYPE zip_rec_type IS RECORD
  6        (zip VARCHAR2(5),
  7         total NUMBER);
  8     zip_rec zip_rec_type;
  9
 10     v_table_name VARCHAR2(20) := '&sv_table_name';
 11     sql_stmt VARCHAR2(500);
 12     v_count NUMBER;
 13  BEGIN
 14     DBMS_OUTPUT.PUT_LINE ('Totals from '||v_table_name||
 15                           ' table');
 16     sql_stmt := 'SELECT zip, COUNT(*) total'||
 17                 '  FROM '||v_table_name||' '||
 18                 'GROUP BY zip';
 19     v_count := 0;
 20     OPEN zip_cur FOR sql_stmt;
 21     LOOP
 22        FETCH zip_cur INTO zip_rec;
 23        EXIT WHEN zip_cur%NOTFOUND;
 24
 25        -- Limit the number of lines printed on the
 26        -- screen to 10
 27        v_count := v_count + 1;
 28        IF v_count <= 10 THEN
 29           DBMS_OUTPUT.PUT_LINE ('Zip code: '||zip_rec.zip||
 30                                 ' Total: '||zip_rec.total);
 31        END IF;
 32     END LOOP;
 33     CLOSE zip_cur;
 34
 35  EXCEPTION
 36     WHEN OTHERS THEN
 37        IF zip_cur%ISOPEN THEN
 38           CLOSE zip_cur;
 39        END IF;
 40
 41        DBMS_OUTPUT.PUT_LINE ('ERROR: '||   SUBSTR(SQLERRM, 1, 200));
 42  END;
 43    /
Enter value for sv_table_name: student
old  10:    v_table_name VARCHAR2(20) := '&sv_table_name';
new  10:    v_table_name VARCHAR2(20) := 'student';
Totals from student table
Zip code: 01247 Total: 1
Zip code: 02124 Total: 1
Zip code: 02155 Total: 1
Zip code: 02189 Total: 5
Zip code: 02563 Total: 1
Zip code: 06483 Total: 1
Zip code: 06605 Total: 1
Zip code: 06798 Total: 1
Zip code: 06820 Total: 3
Zip code: 06830 Total: 3