Excellent: exquisite SQL statements

Note: copy a table (only copy structure, source table name: a new table name: B)
SQL: Select * into B from a where 1 <> 1

Description: copy a table (copy data, source table name: A target table name: B)
SQL: insert into B (a, B, c) Select D, E, F from B;

Note: DisplayArticle, Submitted and last reply time
SQL: select a. Title, A. username, B. adddate from Table A, (select max (adddate) adddate from table where table. Title = A. Title) B

Description: External join query (table name 1: Table A name 2: B)
SQL: select a. a, a. B, A. C, B. C, B. D, B. F from a left out join B on A. A = B. C

Note: Five minutes in advance of the schedule
SQL: Select * from Schedule where datediff ('minute ', F Start Time, getdate ()> 5

Note: Two associated tables are used to delete information that is already unavailable to the primary table in the secondary table.
SQL:
Delete from info where not exists (select * From infobz where info. INFID = infobz. INFID)

Note :--
SQL:
Select. num,. name, B. upd_date, B. prev_upd_date from Table1, (select X. num, X. upd_date, Y. upd_date prev_upd_date from (select num, upd_date, inbound_qty, stock_onhand from Table2 where to_char (upd_date, 'yyyy/mm') = to_char (sysdate, 'yyyy/mm') X, (select num, upd_date, stock_onhand from Table2 where to_char (upd_date, 'yyyy/mm') = to_char (to_date (to_char (sysdate, 'yyyy/mm ') interval between '/01', 'yyyy/MM/dd')-1, 'yyyy/mm') y, where X. num = y. num (+) and X. inbound_qty + nvl (Y. stock_onhand, 0) <> X. stock_onhand) B where. num = B. num

Note :--
SQL:
Select * From studentinfo where not exists (select * from student where studentinfo. id = student. ID) and Department name = '"& strdepartmentname &"' and major name = '"& strinclusionname &" 'order by gender, student source, total score of the College Entrance Examination

Note:
Go to the telephone fee statistics of each unit from the database for one year (two sources of the fixed telephone fee congratulation fertilizer List)
SQL:
Select. userper,. tel,. standbench, to_char (. telfeedate, 'yyyy') as telyear, sum (decode (to_char (. telfeedate, 'mm'), '01',. factration) as Jan, sum (decode (to_char (. telfeedate, 'mm'), '02',. factration) as Fri, sum (decode (to_char (. telfeedate, 'mm'), '03',. factration) as MAR, sum (decode (to_char (. telfeedate, 'mm'), '04 ',. factration) as Apr, sum (decode (to_char (. telfeedate, 'mm'), '05 ',. factration) as may, sum (decode (to_char (. telfeedate, 'mm'), '06',. factration) as Jue, sum (decode (to_char (. telfeedate, 'mm'), '07 ',. factration) as Jul, sum (decode (to_char (. telfeedate, 'mm'), '08 ',. factration) as Agu, sum (decode (to_char (. telfeedate, 'mm'), '09',. factration) as SEP, sum (decode (to_char (. telfeedate, 'mm'), '10',. factration) as Oct, sum (decode (to_char (. telfeedate, 'mm'), '11',. factration) as Nov, sum (decode (to_char (. telfeedate, 'mm'), '12',. factration) as DEC from (select. userper,. tel,. standyet, B. telfeedate, B. factration from telfeestand A, telstmb where. tel = B. telfax) a group by. userper,. tel,. standbench, to_char (. telfeedate, 'yyyy ')

Notes: Four-table join query problems:
SQL: Select * from a left inner join B on. A = B. B right inner join C on. A = C. C inner join D on. A = D. d Where .....

Note: Obtain the smallest unused ID number in the table.
SQL:
Select (case when exists (select * From handle B where B. handleid = 1) Then min (handleid) + 1 else 1 end) as handleid from handle where not handleid in (select. handleid-1 from handle)