ͬһ¸ö½»²æ±íµÄ¶¯Ì¬SQLʵÏÖ
DECLARE
TYPE list IS TABLE OF t_stu.project%TYPE INDEX BY BINARY_INTEGER;
project_list list;
v_pro_num NUMBER;
sql_str VARCHAR(255);
t_stu
SID SUBJECT SCORE
1 Êýѧ 99
1 Ó¢Óï 68
1 ·¨ÂÉ 79
2 Êýѧ 92
2 Ó¢Óï 72
2 ·¨ÂÉ 96
ʵÏÖ======
SID
Êýѧ
Ó¢Óï
·¨ÂÉ
1
99
68
79
2
92
72
96
DECLARE
TYPE list IS TABLE OF t_stu.subject%TYPE INDEX BY BINARY_INTEGER;
subject_list list;
v_pro_num NUMBER;
sql_str VARCHAR(255);
BEGIN
SELECT COUNT(DISTINCT subject) INTO v_pro_num from t_stu;
sql_str := 'SELECT id ';
FOR v_idx in 1..v_pro_num LOOP
IF v_idx = 1 THEN
SELECT DISTINCT subject INTO subject_list(v_idx) from t_stu WHERE rownum = 1;
ELSE
SELECT subjectINTO subject_list(v_idx)
from (SELECT DISTINCT subject, rownum row_num from t_stu WHERE rownum < v_idx + 1)
WHERE row_num = v_idx;
END IF;
sql_str := sql_str || ', SUM(DECODE(subject,''' || subject_list(v_idx) || ''',score,0)) AS ' || subject_list(v_idx);
END LOOP;
sql_str := sql_str || ' from t_stu GROUP BY id';
DBMS_OUTPUT.PUT_LINE('sql--->' || sql_str);
EXEC IMMEDIATE sql_str;
&
Ïà¹ØÎĵµ£º
ÔÚT-sqlµÄд·¨ÉÏÓкܴóµÄ½²¾¿£¬ÏÂÃæÁгö³£¼ûµÄÒªµã£ºÊ×ÏÈ£¬DBMS´¦Àí²éѯ¼Æ»®µÄ¹ý³ÌÊÇÕâÑùµÄ£º
1¡¢²éѯÓï¾äµÄ´Ê·¨¡¢Óï·¨¼ì²é
2¡¢½«Óï¾äÌá½»¸øDBMSµÄ²éѯÓÅ»¯Æ÷
3¡¢ÓÅ»¯Æ÷×ö´úÊýÓÅ»¯ºÍ´æÈ¡Â·¾¶µÄÓÅ»¯
4¡¢ÓÉÔ¤±àÒëÄ£¿éÉú³É²éѯ¹æ»®
5¡¢È»ºóÔÚºÏÊʵÄʱ¼äÌá½»¸øÏµÍ³´¦ÀíÖ´ÐÐ
6¡¢×îºó½«Ö´Ðнá¹û·µ»Ø¸øÓû§¡£
Æä´Î£¬¿´Ò»ÏÂS ......
CyberSavvy ¼áÐÅÈí¼þ×Ô¶¯»¯¿ÉÒÔÈÿͻ§ÇáËÉÏíÊÜÉú»î¡£DataPlace ÊǸù«Ë¾µÄÈí¼þ¼´·þÎñ½â¾ö·½°¸£¬Ò²¿É³ÆÖ®Îª“Êý¾Ý¿â¹¤³§”£¬ËüÄܹ»ÈÃÃæÏò¼¼ÊõÒÔ¼°ÃæÏòÉÌÎñµÄÓû§´´½¨²¢ÐÞ¸Ä×Ô¼ºµÄÊý¾Ý¿â£¬¶øCyberSavvy ¹«Ë¾½«Îª¸ÃÊý¾Ý¿âÌṩÍйܷþÎñ¡£Òò´ËCyberSavvy ¹«Ë¾ÐèÒªÅÍʯ°ã¼á¹ÌµÄÊý¾Ý¿â£¬²¢Í¨¹ýÍòÎÞһʧµÄÊý¾Ý´«Êä»úÖÆÀ´Ö ......
Student(S#,Sname,Sage,Ssex) ѧÉú±í
Course(C#,Cname,T#) ¿Î³Ì±í
SC(S#,C#,score) ³É¼¨±í
Teacher(T#,Tname) ½Ìʦ±í
ÎÊÌ⣺
1¡¢²éѯ“”¿Î³Ì±È“”¿Î³Ì³É¼¨¸ßµÄËùÓÐѧÉúµÄѧºÅ£»
SELECT a.S# from (SELECT s#,score from SC WHERE C#='001') a,
(SELECT s#,score fr ......
ÈçºÎÐÞ¸ÄSQL ServerµÄÁ¬½ÓÊý
ÎÒ°ÑSQL Server 7.0µÄÓû§Á¬½ÓÊýÉèΪ1ºó£¬Êý¾Ý¿â¾ÍÔÙÒ²Á¬²»ÉÏÁË£¬ËùÒÔҲû°ì·¨ÐÞ¸ÄÁ¬½ÓÊý
ÇëÎÊÓÐʲô°ì·¨ÄÜÐÞ¸ÄÁ¬½ÓÊý£¿
ÔÚserver µÄÊôÐÔÀïÃæÓиöconnetctions µÄ
maximun concurr ......
ÎÞÂÛÄúÊÇһλ SQL µÄÐÂÊÖ£¬»òÊÇһλֻÊÇÐèÒª¶Ô SQL ¸´Ï°Ò»ÏµÄ×ÊÁϲִ¢Òµ½çÀϽ«£¬Äú¾ÍÀ´¶ÔµØ·½ÁË£¡
- SQL Ö¸Áî: SQL ÈçºÎ±»ÓÃÀ´´¢´æ¡¢¶ÁÈ¡¡¢ÒÔ¼°´¦ÀíÊý¾Ý¿âÖ®ÖеÄ×ÊÁÏ¡£
- ±í¸ñ´¦Àí: SQL ÈçºÎ±»ÓÃÀ´´¦ÀíÊý¾Ý¿âÖеıí¸ñ¡£
- SQLÓï·¨: ÕâÒ»Ò³ÁгöËùÓÐÔÚÕâ¸ö½Ì²ÄÖб»Ìáµ½µÄ SQL Óï·¨
SQL SELECT
Store_Information ±í¸ñ ......