1 oracle常用经典SQL查询
2 常用SQL查询：
3
4 1、查看表空间的名称及大小
5
6 select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size
7 from dba_tablespaces t, dba_data_files d
8 where t.tablespace_name = d.tablespace_name
9 group by t.tablespace_name;
10
11 2、查看表空间物理文件的名称及大小
12
13 select tablespace_name, file_id, file_name,
14 round(bytes/(1024*1024),0) total_space
15 from dba_data_files
16 order by tablespace_name;
17
18 3、查看回滚段名称及大小
19
20 select segment_name, tablespace_name, r.status,
21 (initial_extent/1024) InitialExtent,(next_extent/1024) NextExtent,
22 max_extents, v.curext CurExtent
23 From dba_rollback_segs r, v$rollstat v
24 Where r.segment_id = v.usn(+)
25 order by segment_name;
26
27 4、查看控制文件
28
29 select name from v$controlfile;
30
31 5、查看日志文件
32
33 select member from v$logfile;
34
35 6、查看表空间的使用情况
36
37 select sum(bytes)/(1024*1024) as free_space,tablespace_name
38 from dba_free_space
39 group by tablespace_name;
40
41 SELECT A.TABLESPACE_NAME,A.BYTES TOTAL,B.BYTES USED, C.BYTES FREE,
42 (B.BYTES*100)/A.BYTES "% USED",(C.BYTES*100)/A.BYTES "% FREE"
43 FROM SYS.SM$TS_AVAIL A,SYS.SM$TS_USED B,SYS.SM$TS_FREE C
44 WHERE A.TABLESPACE_NAME=B.TABLESPACE_NAME AND A.TABLESPACE_NAME=C.TABLESPACE_NAME;
45
46 7、查看数据库库对象
47
48 select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;
49
50 8、查看数据库的版本
51
52 Select version FROM Product_component_version
53 Where SUBSTR(PRODUCT,1,6)=‘Oracle‘;
54
55 9、查看数据库的创建日期和归档方式
56
57 Select Created, Log_Mode, Log_Mode From V$Database;
58
59 10、捕捉运行很久的SQL
60
61 column username format a12
62 column opname format a16
63 column progress format a8
64
65 select username,sid,opname,
66 round(sofar*100 / totalwork,0) || ‘%‘ as progress,
67 time_remaining,sql_text
68 from v$session_longops , v$sql
69 where time_remaining <> 0
70 and sql_address = address
71 and sql_hash_value = hash_value
72 /
73 11。查看数据表的参数信息
74 SELECT partition_name, high_value, high_value_length, tablespace_name,
75 pct_free, pct_used, ini_trans, max_trans, initial_extent,
76 next_extent, min_extent, max_extent, pct_increase, FREELISTS,
77 freelist_groups, LOGGING, BUFFER_POOL, num_rows, blocks,
78 empty_blocks, avg_space, chain_cnt, avg_row_len, sample_size,
79 last_analyzed
80 FROM dba_tab_partitions
81 --WHERE table_name = :tname AND table_owner = :towner
82 ORDER BY partition_position
83
84 12.查看还没提交的事务
85 select * from v$locked_object;
86 select * from v$transaction;
87
88 13。查找object为哪些进程所用
89 select
90 p.spid,
91 s.sid,
92 s.serial# serial_num,
93 s.username user_name,
94 a.type object_type,
95 s.osuser os_user_name,
96 a.owner,
97 a.object object_name,
98 decode(sign(48 - command),
99 1,
100 to_char(command), ‘Action Code #‘ || to_char(command) ) action,
101 p.program oracle_process,
102 s.terminal terminal,
103 s.program program,
104 s.status session_status
105 from v$session s, v$access a, v$process p
106 where s.paddr = p.addr and
107 s.type = ‘USER‘ and
108 a.sid = s.sid and
109 a.object=‘SUBSCRIBER_ATTR‘
110 order by s.username, s.osuser
111
112 14。回滚段查看
113 select rownum, sys.dba_rollback_segs.segment_name Name, v$rollstat.extents
114 Extents, v$rollstat.rssize Size_in_Bytes, v$rollstat.xacts XActs,
115 v$rollstat.gets Gets, v$rollstat.waits Waits, v$rollstat.writes Writes,
116 sys.dba_rollback_segs.status status from v$rollstat, sys.dba_rollback_segs,
117 v$rollname where v$rollname.name(+) = sys.dba_rollback_segs.segment_name and
118 v$rollstat.usn (+) = v$rollname.usn order by rownum
119
120 15。耗资源的进程（top session）
121 select s.schemaname schema_name, decode(sign(48 - command), 1,
122 to_char(command), ‘Action Code #‘ || to_char(command) ) action, status
123 session_status, s.osuser os_user_name, s.sid, p.spid , s.serial# serial_num,
124 nvl(s.username, ‘[Oracle process]‘) user_name, s.terminal terminal,
125 s.program program, st.value criteria_value from v$sesstat st, v$session s , v$process p
126 where st.sid = s.sid and st.statistic# = to_number(‘38‘) and (‘ALL‘ = ‘ALL‘
127 or s.status = ‘ALL‘) and p.addr = s.paddr order by st.value desc, p.spid asc, s.username asc, s.osuser asc
128
129 16。查看锁（lock）情况
130 select /*+ RULE */ ls.osuser os_user_name, ls.username user_name,
131 decode(ls.type, ‘RW‘, ‘Row wait enqueue lock‘, ‘TM‘, ‘DML enqueue lock‘, ‘TX‘,
132 ‘Transaction enqueue lock‘, ‘UL‘, ‘User supplied lock‘) lock_type,
133 o.object_name object, decode(ls.lmode, 1, null, 2, ‘Row Share‘, 3,
134 ‘Row Exclusive‘, 4, ‘Share‘, 5, ‘Share Row Exclusive‘, 6, ‘Exclusive‘, null)
135 lock_mode, o.owner, ls.sid, ls.serial# serial_num, ls.id1, ls.id2
136 from sys.dba_objects o, ( select s.osuser, s.username, l.type,
137 l.lmode, s.sid, s.serial#, l.id1, l.id2 from v$session s,
138 v$lock l where s.sid = l.sid ) ls where o.object_id = ls.id1 and o.owner
139 <> ‘SYS‘ order by o.owner, o.object_name
140
141 17。查看等待（wait）情况
142 SELECT v$waitstat.class, v$waitstat.count count, SUM(v$sysstat.value) sum_value
143 FROM v$waitstat, v$sysstat WHERE v$sysstat.name IN (‘db block gets‘,
144 ‘consistent gets‘) group by v$waitstat.class, v$waitstat.count
145
146 18。查看sga情况
147 SELECT NAME, BYTES FROM SYS.V_$SGASTAT ORDER BY NAME ASC
148
149 19。查看catched object
150 SELECT owner, name, db_link, namespace,
151 type, sharable_mem, loads, executions,
152 locks, pins, kept FROM v$db_object_cache
153
154 20。查看V$SQLAREA
155 SELECT SQL_TEXT, SHARABLE_MEM, PERSISTENT_MEM, RUNTIME_MEM, SORTS,
156 VERSION_COUNT, LOADED_VERSIONS, OPEN_VERSIONS, USERS_OPENING, EXECUTIONS,
157 USERS_EXECUTING, LOADS, FIRST_LOAD_TIME, INVALIDATIONS, PARSE_CALLS, DISK_READS,
158 BUFFER_GETS, ROWS_PROCESSED FROM V$SQLAREA
159
160 21。查看object分类数量
161 select decode (o.type#,1,‘INDEX‘ , 2,‘TABLE‘ , 3 , ‘CLUSTER‘ , 4, ‘VIEW‘ , 5 ,
162 ‘SYNONYM‘ , 6 , ‘SEQUENCE‘ , ‘OTHER‘ ) object_type , count(*) quantity from
163 sys.obj$ o where o.type# > 1 group by decode (o.type#,1,‘INDEX‘ , 2,‘TABLE‘ , 3
164 , ‘CLUSTER‘ , 4, ‘VIEW‘ , 5 , ‘SYNONYM‘ , 6 , ‘SEQUENCE‘ , ‘OTHER‘ ) union select
165 ‘COLUMN‘ , count(*) from sys.col$ union select ‘DB LINK‘ , count(*) from
166
167 22。按用户查看object种类
168 select u.name schema, sum(decode(o.type#, 1, 1, NULL)) indexes,
169 sum(decode(o.type#, 2, 1, NULL)) tables, sum(decode(o.type#, 3, 1, NULL))
170 clusters, sum(decode(o.type#, 4, 1, NULL)) views, sum(decode(o.type#, 5, 1,
171 NULL)) synonyms, sum(decode(o.type#, 6, 1, NULL)) sequences,
172 sum(decode(o.type#, 1, NULL, 2, NULL, 3, NULL, 4, NULL, 5, NULL, 6, NULL, 1))
173 others from sys.obj$ o, sys.user$ u where o.type# >= 1 and u.user# =
174 o.owner# and u.name <> ‘PUBLIC‘ group by u.name order by
175 sys.link$ union select ‘CONSTRAINT‘ , count(*) from sys.con$
176
177 23。有关connection的相关信息
178 1）查看有哪些用户连接
179 select s.osuser os_user_name, decode(sign(48 - command), 1, to_char(command),
180 ‘Action Code #‘ || to_char(command) ) action, p.program oracle_process,
181 status session_status, s.terminal terminal, s.program program,
182 s.username user_name, s.fixed_table_sequence activity_meter, ‘‘ query,
183 0 memory, 0 max_memory, 0 cpu_usage, s.sid, s.serial# serial_num
184 from v$session s, v$process p where s.paddr=p.addr and s.type = ‘USER‘
185 order by s.username, s.osuser
186 2）根据v.sid查看对应连接的资源占用等情况
187 select n.name,
188 v.value,
189 n.class,
190 n.statistic#
191 from v$statname n,
192 v$sesstat v
193 where v.sid = 71 and
194 v.statistic# = n.statistic#
195 order by n.class, n.statistic#
196 3）根据sid查看对应连接正在运行的sql
197 select /*+ PUSH_SUBQ */
198 command_type,
199 sql_text,
200 sharable_mem,
201 persistent_mem,
202 runtime_mem,
203 sorts,
204 version_count,
205 loaded_versions,
206 open_versions,
207 users_opening,
208 executions,
209 users_executing,
210 loads,
211 first_load_time,
212 invalidations,
213 parse_calls,
214 disk_reads,
215 buffer_gets,
216 rows_processed,
217 sysdate start_time,
218 sysdate finish_time,
219 ‘>‘ || address sql_address,
220 ‘N‘ status
221 from v$sqlarea
222 where address = (select sql_address from v$session where sid = 71)
223
224 24．查询表空间使用情况
225 select a.tablespace_name "表空间名称",
226 100-round((nvl(b.bytes_free,0)/a.bytes_alloc)*100,2) "占用率(%)",
227 round(a.bytes_alloc/1024/1024,2) "容量(M)",
228 round(nvl(b.bytes_free,0)/1024/1024,2) "空闲(M)",
229 round((a.bytes_alloc-nvl(b.bytes_free,0))/1024/1024,2) "使用(M)",
230 Largest "最大扩展段(M)",
231 to_char(sysdate,‘yyyy-mm-dd hh24:mi:ss‘) "采样时间"
232 from (select f.tablespace_name,
233 sum(f.bytes) bytes_alloc,
234 sum(decode(f.autoextensible,‘YES‘,f.maxbytes,‘NO‘,f.bytes)) maxbytes
235 from dba_data_files f
236 group by tablespace_name) a,
237 (select f.tablespace_name,
238 sum(f.bytes) bytes_free
239 from dba_free_space f
240 group by tablespace_name) b,
241 (select round(max(ff.length)*16/1024,2) Largest,
242 ts.name tablespace_name
243 from sys.fet$ ff, sys.file$ tf,sys.ts$ ts
244 where ts.ts#=ff.ts# and ff.file#=tf.relfile# and ts.ts#=tf.ts#
245 group by ts.name, tf.blocks) c
246 where a.tablespace_name = b.tablespace_name and a.tablespace_name = c.tablespace_name
247
248 25. 查询表空间的碎片程度
249
250 select tablespace_name,count(tablespace_name) from dba_free_space group by tablespace_name
251 having count(tablespace_name)>10;
252
253 alter tablespace name coalesce;
254 alter table name deallocate unused;
255
256 create or replace view ts_blocks_v as
257 select tablespace_name,block_id,bytes,blocks,‘free space‘ segment_name from dba_free_space
258 union all
259 select tablespace_name,block_id,bytes,blocks,segment_name from dba_extents;
260
261 select * from ts_blocks_v;
262
263 select tablespace_name,sum(bytes),max(bytes),count(block_id) from dba_free_space
264 group by tablespace_name;
265
266 26。查询有哪些数据库实例在运行
267 select inst_name from v$active_instances;
268
269 ===========================================================
270 ######### 创建数据库----look $ORACLE_HOME/rdbms/admin/buildall.sql #############
271
272 create database db01
273 maxlogfiles 10
274 maxdatafiles 1024
275 maxinstances 2
276 logfile
277 GROUP 1 (‘/u01/oradata/db01/log_01_db01.rdo‘) SIZE 15M,
278 GROUP 2 (‘/u01/oradata/db01/log_02_db01.rdo‘) SIZE 15M,
279 GROUP 3 (‘/u01/oradata/db01/log_03_db01.rdo‘) SIZE 15M,
280 datafile ‘u01/oradata/db01/system_01_db01.dbf‘) SIZE 100M,
281 undo tablespace UNDO
282 datafile ‘/u01/oradata/db01/undo_01_db01.dbf‘ SIZE 40M
283 default temporary tablespace TEMP
284 tempfile ‘/u01/oradata/db01/temp_01_db01.dbf‘ SIZE 20M
285 extent management local uniform size 128k
286 character set AL32UTE8
287 national character set AL16UTF16
288 set time_zone=‘America/New_York‘;
289
290 ############### 数据字典 ##########
291
292 set wrap off
293
294 select * from v$dba_users;
295
296 grant select on table_name to user/rule;
297
298 select * from user_tables;
299
300 select * from all_tables;
301
302 select * from dba_tables;
303
304 revoke dba from user_name;
305
306 shutdown immediate
307
308 startup nomount
309
310 select * from v$instance;
311
312 select * from v$sga;
313
314 select * from v$tablespace;
315
316 alter session set nls_language=american;
317
318 alter database mount;
319
320 select * from v$database;
321
322 alter database open;
323
324 desc dictionary
325
326 select * from dict;
327
328 desc v$fixed_table;
329
330 select * from v$fixed_table;
331
332 set oracle_sid=foxconn
333
334 select * from dba_objects;
335
336 set serveroutput on
337
338 execute dbms_output.put_line(‘sfasd‘);
339
340 ############# 控制文件 ###########
341
342 select * from v$database;
343
344 select * from v$tablespace;
345
346 select * from v$logfile;
347
348 select * from v$log;
349
350 select * from v$backup;
351
352 /*备份用户表空间*/
353 alter tablespace users begin backup;
354
355 select * from v$archived_log;
356
357 select * from v$controlfile;
358
359 alter system set control_files=‘$ORACLE_HOME/oradata/u01/ctrl01.ctl‘,
360 ‘$ORACLE_HOME/oradata/u01/ctrl02.ctl‘ scope=spfile;
361
362 cp $ORACLE_HOME/oradata/u01/ctrl01.ctl $ORACLE_HOME/oradata/u01/ctrl02.ctl
363
364 startup pfile=‘../initSID.ora‘
365
366 select * from v$parameter where name like ‘control%‘ ;
367
368 show parameter control;
369
370 select * from v$controlfile_record_section;
371
372 select * from v$tempfile;
373
374 /*备份控制文件*/
375 alter database backup controlfile to ‘../filepath/control.bak‘;
376
377 /*备份控制文件，并将二进制控制文件变为了asc 的文本文件*/
378 alter database backup controlfile to trace;
379
380 ############### redo log ##############
381
382 archive log list;
383
384 alter system archive log start;--启动自动存档
385
386 alter system switch logfile;--强行进行一次日志switch
387
388 alter system checkpoint;--强制进行一次checkpoint
389
390 alter tablspace users begin backup;
391
392 alter tablespace offline;
393
394 /*checkpoint 同步频率参数FAST_START_MTTR_TARGET,同步频率越高，系统恢复所需时间越短*/
395 show parameter fast;
396
397 show parameter log_checkpoint;
398
399 /*加入一个日志组*/
400 alter database add logfile group 3 (‘/$ORACLE_HOME/oracle/ora_log_file6.rdo‘ size 10M);
401
402 /*加入日志组的一个成员*/
403 alter database add logfile member ‘/$ORACLE_HOME/oracle/ora_log_file6.rdo‘ to group 3;
404
405 /*删除日志组:当前日志组不能删；活动的日志组不能删；非归档的日志组不能删*/
406 alter database drop logfile group 3;
407
408 /*删除日志组中的某个成员，但每个组的最后一个成员不能被删除*/
409 alter databse drop logfile member ‘$ORACLE_HOME/oracle/ora_log_file6.rdo‘;
410
411 /*清除在线日志*/
412 alter database clear logfile ‘$ORACLE_HOME/oracle/ora_log_file6.rdo‘;
413
414 alter database clear logfile group 3;
415
416 /*清除非归档日志*/
417 alter database clear unarchived logfile group 3;
418
419 /*重命名日志文件*/
420 alter database rename file ‘$ORACLE_HOME/oracle/ora_log_file6.rdo‘ to ‘$ORACLE_HOME/oracle/ora_log_file6a.rdo‘;
421
422 show parameter db_create;
423
424 alter system set db_create_online_log_dest_1=‘path_name‘;
425
426 select * from v$log;
427
428 select * from v$logfile;
429
430 /*数据库归档模式到非归档模式的互换,要启动到mount状态下才能改变;startup mount;然后再打开数据库.*/
431 alter database noarchivelog/archivelog;
432
433 achive log start;---启动自动归档
434
435 alter system archive all;－－手工归档所有日志文件
436
437 select * from v$archived_log;
438
439 show parameter log_archive;
440
441 ###### 分析日志文件logmnr ##############
442
443 1) 在init.ora中set utl_file_dir 参数
444 2) 重新启动oracle
445 3) create 目录文件
446 desc dbms_logmnr_d;
447 dbms_logmnr_d.build;
448 4) 加入日志文件 add/remove log file
449 dhms_logmnr.add_logfile
450 dbms_logmnr.removefile
451 5) start logmnr
452 dbms_logmnr.start_logmnr
453 6) 分析出来的内容查询 v$logmnr_content --sqlredo/sqlundo
454
455 实践：
456
457 desc dbms_logmnr_d;
458
459 /*对数据表做一些操作，为恢复操作做准备*/
460 update 表 set qty=10 where stor_id=6380;
461
462 delete 表 where stor_id=7066;
463 /***********************************/
464 utl_file_dir的路径
465 execute dbms_logmnr_d.build(‘foxdict.ora‘,‘$ORACLE_HOME/oracle/admin/fox/cdump‘);
466
467 execute dbms_logmnr.add_logfile(‘$ORACLE_HOME/oracle/ora_log_file6.log‘,dbms_logmnr.newfile);
468
469 execute dbms_logmnr.start_logmnr(dictfilename=>‘$ORACLE_HOME/oracle/admin/fox/cdump/foxdict.ora‘);
470
471 ######### tablespace ##############
472
473 select * form v$tablespace;
474
475 select * from v$datafile;
476
477 /*表空间和数据文件的对应关系*/
478 select t1.name,t2.name from v$tablespace t1,v$datafile t2 where t1.ts#=t2.ts#;
479
480 alter tablespace users add datafile ‘path‘ size 10M;
481
482 select * from dba_rollback_segs;
483
484 /*限制用户在某表空间的使用限额*/
485 alter user user_name quota 10m on tablespace_name;
486
487 create tablespace xxx [datafile ‘path_name/datafile_name‘] [size xxx] [extent management local/dictionary] [default storage(xxx)];
488
489 exmple: create tablespace userdata datafile ‘$ORACLE_HOME/oradata/userdata01.dbf‘ size 100M AUTOEXTEND ON NEXT 5M MAXSIZE 200M;
490 create tablespace userdata datafile ‘$ORACLE_HOME/oradata/userdata01.dbf‘ size 100M extent management dictionary default storage(initial 100k next 100k pctincrease 10) offline;
491 /*9i以后，oracle建议使用local管理，而不使用dictionary管理，因为local采用bitmap管理表空间 ，不会产生系统表空间的自愿争用;*/
492 create tablespace userdata datafile ‘$ORACLE_HOME/oradata/userdata01.dbf‘ size 100M extent management local uniform size 1m;
493 create tablespace userdata datafile ‘$ORACLE_HOME/oradata/userdata01.dbf‘ size 100M extent management local autoallocate;
494 /*在创建表空间时，设置表空间内的段空间管理模式，这里用的是自动管理*/
495 create tablespace userdata datafile ‘$ORACLE_HOME/oradata/userdata01.dbf‘ size 100M extent management local uniform size 1m segment space management auto;
496
497 alter tablespace userdata mininum extent 10;
498
499 alter tablespace userdata default storage(initial 1m next 1m pctincrease 20);
500
501 /*undo tablespace(不能被用在字典管理模下) */
502 create undo tablespace undo1 datafile ‘$ORACLE_HOME/oradata/undo101.dbf‘ size 40M extent management local;
503
504 show parameter undo;
505
506 /*temporary tablespace*/
507 create temporary tablespace userdata tempfile ‘$ORACLE_HOME/oradata/undo101.dbf‘ size 10m extent management local;
508
509 /*设置数据库缺省的临时表空间*/
510 alter database default temporary tablespace tablespace_name;
511
512 /*系统/临时/在线的undo表空间不能被offline*/
513 alter tablespace tablespace_name offline/online;
514
515 alter tablespace tablespace_name read only;
516
517 /*重命名用户表空间*/
518 alter tablespace tablespace_name rename datafile ‘$ORACLE_HOME/oradata/undo101.dbf‘ to ‘$ORACLE_HOME/oradata/undo102.dbf‘;
519
520 /*重命名系统表空间 ,但在重命名前必须将数据库shutdown,并重启到mount状态*/
521 alter database rename file ‘$ORACLE_HOME/oradata/system01.dbf‘ to ‘$ORACLE_HOME/oradata/system02.dbf‘;
522
523 drop tablespace userdata including contents and datafiles;---drop tablespce
524
525 /*resize tablespace,autoextend datafile space*/
526 alter database datafile ‘$ORACLE_HOME/oradata/undo102.dbf‘ autoextend on next 10m maxsize 500M;
527
528 /*resize datafile*/
529 alter database datafile ‘$ORACLE_HOME/oradata/undo102.dbf‘ resize 50m;
530
531 /*给表空间扩展空间*/
532 alter tablespace userdata add datafile ‘$ORACLE_HOME/oradata/undo102.dbf‘ size 10m;
533
534 /*将表空间设置成OMF状态*/
535 alter system set db_create_file_dest=‘$ORACLE_HOME/oradata‘;
536
537 create tablespace userdata;---use OMF status to create tablespace;
538
539 drop tablespace userdata;---user OMF status to drop tablespace;
540
541 select * from dba_tablespace/v$tablespace/dba_data_files;
542
543 /*将表的某分区移动到另一个表空间*/
544 alter table table_name move partition partition_name tablespace tablespace_name;
545
546 ###### ORACLE storage structure and relationships #########
547
548 /*手工分配表空间段的分区(extend)大小*/
549 alter table kong.test12 allocate extent(size 1m datafile ‘$ORACLE_HOME/oradata/undo102.dbf‘);
550
551 alter table kong.test12 deallocate unused; ---释放表中没有用到的分区
552
553 show parameter db;
554
555 alter system set db_8k_cache_size=10m; ---配置8k块的内存空间块参数
556
557 select * from dba_extents/dba_segments/data_tablespace;
558
559 select * from dba_free_space/dba_data_file/data_tablespace;
560
561 /*数据对象所占用的字节数*/
562 select sum(bytes) from dba_extents where onwer=‘kong‘ and segment_name =‘table_name‘;
563
564 ############ UNDO Data ################
565
566 show parameter undo;
567
568 alter tablespace users offline normal;
569
570 alter tablespace users offline immediate;
571
572 recover datafile ‘$ORACLE_HOME/oradata/undo102.dbf‘;
573
574 alter tablespace users online ;
575
576 select * from dba_rollback_segs;
577
578 alter system set undo_tablespace=undotbs1;
579
580 /*忽略回滚段的错误提示*/
581 alter system set undo_suppress_errors=true;
582
583 /*在自动管理模式下,不会真正建立rbs1;在手工管理模式则可以建立,且是私有回滚段*/
584 create rollback segment rbs1 tablespace undotbs;
585
586 desc dbms_flashback;
587
588 /*在提交了修改的数据后,9i提供了旧数据的回闪操作,将修改前的数据只读给用户看,但这部分数据不会又恢复在表中,而是旧数据的一个映射*/
589 execute dbms_flashback.enable_at_time(‘26-JAN-04:12:17:00 pm‘);
590
591 execute dbms_flashback.disable;
592
593 /*回滚段的统计信息*/
594 select end_time,begin_time,undoblks from v$undostat;
595
596 /*undo表空间的大小计算公式: UndoSpace=[UR * (UPS * DBS)] + (DBS * 24)
597 UR :UNDO_RETENTION 保留的时间(秒)
598 UPS :每秒的回滚数据块
599 DBS:系统EXTENT和FILE SIZE(也就是db_block_size)*/
600
601 select * from dba_rollback_segs/v$rollname/v$rollstat/v$undostat/v$session/v$transaction;
602
603 show parameter transactions;
604
605 show parameter rollback;
606
607 /*在手工管理模式下,建立公共的回滚段*/
608 create public rollback segment prbs1 tablespace undotbs;
609
610 alter rollback segment rbs1 online;----在手工管理模式
611
612 /*在手工管理模式中,initSID.ora中指定 undo_management=manual 、rollback_segment=(‘rbs1‘,‘rbs2‘,...)、
613 transactions=100 、transactions_per_rollback_segment=10
614 然后 shutdown immediate ,startup pfile=....\???.ora */
615
616 ########## Managing Tables ###########
617
618 /*char type maxlen=2000;varchar2 type maxlen=4000 bytes
619 rowid 是18位的64进制字符串 (10个bytes 80 bits)
620 rowid组成: object#(对象号)--32bits,6位
621 rfile#(相对文件号)--10bits,3位
622 block#(块号)--22bits,6位
623 row#(行号)--16bits,3位
624 64进制: A-Z,a-z,0-9,/,+ 共64个符号
625
626 dbms_rowid 包中的函数可以提供对rowid的解释*/
627
628 select rowid,dbms_rowid.rowid_block_number(rowid),dbms_rowid.rowid_row_number(rowid) from table_name;
629
630 create table test2
631 (
632 id int,
633 lname varchar2(20) not null,
634 fname varchar2(20) constraint ck_1 check(fname like ‘k%‘),
635 empdate date default sysdate)
636 ) tablespace tablespace_name;
637
638
639 create global temporary table test2 on commit delete/preserve rows as select * from kong.authors;
640
641 create table user.table(...) tablespace tablespace_name storage(...) pctfree10 pctused 40;
642
643 alter table user.tablename pctfree 20 pctused 50 storage(...);---changing table storage
644
645 /*手工分配分区,分配的数据文件必须是表所在表空间内的数据文件*/
646 alter table user.table_name allocate extent(size 500k datafile ‘...‘);
647
648 /*释放表中没有用到的空间*/
649 alter table table_name deallocate unused;
650
651 alter table table_name deallocate unused keep 8k;
652
653 /*将非分区表的表空间搬到新的表空间,在移动表空间后，原表中的索引对象将会不可用，必须重建*/
654 alter table user.table_name move tablespace new_tablespace_name;
655
656 create index index_name on user.table_name(column_name) tablespace users;
657
658 alter index index_name rebuild;
659
660 drop table table_name [CASCADE CONSTRAINTS];
661
662 alter table user.table_name drop column col_name [CASCADE CONSTRAINTS CHECKPOINT 1000];---drop column
663
664 /*给表中不用的列做标记*/
665 alter table user.table_name set unused column comments CASCADE CONSTRAINTS;
666
667 /*drop表中不用的做了标记列*/
668 alter table user.table_name drop unused columns checkpoint 1000;
669
670 /*当在drop col是出现异常，使用CONTINUE，防止重删前面的column*/
671 ALTER TABLE USER.TABLE_NAME DROP COLUMNS CONTINUE CHECKPOINT 1000;
672
673 select * from dba_tables/dba_objects;
674
675 ######## managing indexes ##########
676
677 /*create index*/
678 example:
679 /*创建一般索引*/
680 create index index_name on table_name(column_name) tablespace tablespace_name;
681 /*创建位图索引*/
682 create bitmap index index_name on table_name(column_name1,column_name2) tablespace tablespace_name;
683 /*索引中不能用pctused*/
684 create [bitmap] index index_name on table_name(column_name) tablespace tablespace_name pctfree 20 storage(inital 100k next 100k) ;
685 /*大数据量的索引最好不要做日志*/
686 create [bitmap] index index_name table_name(column_name1,column_name2) tablespace_name pctfree 20 storage(inital 100k next 100k) nologging;
687 /*创建反转索引*/
688 create index index_name on table_name(column_name) reverse;
689 /*创建函数索引*/
690 create index index_name on table_name(function_name(column_name)) tablespace tablespace_name;
691 /*建表时创建约束条件*/
692 create table user.table_name(column_name number(7) constraint constraint_name primary key deferrable using index storage(initial 100k next 100k) tablespace tablespace_name,column_name2 varchar2(25) constraint constraint_name not null,column_name3 number(7)) tablespace tablespace_name;
693
694 /*给创建bitmap index分配的内存空间参数，以加速建索引*/
695 show parameter create_bit;
696
697 /*改变索引的存储参数*/
698 alter index index_name pctfree 30 storage(initial 200k next 200k);
699
700 /*给索引手工分配一个分区*/
701 alter index index_name allocate extent (size 200k datafile ‘$ORACLE/oradata/..‘);
702
703 /*释放索引中没用的空间*/
704 alter index index_name deallocate unused;
705
706 /*索引重建*/
707 alter index index_name rebuild tablespace tablespace_name;
708
709 /*普通索引和反转索引的互换*/
710 alter index index_name rebuild tablespace tablespace_name reverse;
711
712 /*重建索引时，不锁表*/
713 alter index index_name rebuild online;
714
715 /*给索引整理碎片*/
716 alter index index_name COALESCE;
717
718 /*分析索引,事实上是更新统计的过程*/
719 analyze index index_name validate structure;
720
721 desc index_state;
722
723 drop index index_name;
724
725 alter index index_name monitoring usage;-----监视索引是否被用到
726
727 alter index index_name nomonitoring usage;----取消监视
728
729 /*有关索引信息的视图*/
730 select * from dba_indexes/dba_ind_columns/dbs_ind_expressions/v$object_usage;
731
732 ########## 数据完整性的管理(Maintaining data integrity) ##########
733
734 alter table table_name drop constraint constraint_name;----drop 约束
735
736 alter table table_name add constraint constraint_name primary key(column_name1,column_name2);-----创建主键
737
738 alter table table_name add constraint constraint_name unique(column_name1,column_name2);---创建唯一约束
739
740 /*创建外键约束*/
741 alter table table_name add constraint constraint_name foreign key(column_name1) references table_name(column_name1);
742
743 /*不效验老数据，只约束新的数据[enable/disable：约束/不约束新数据;novalidate/validate:不对/对老数据进行验证]*/
744 alter table table_name add constraint constraint_name check(column_name like ‘B%‘) enable/disable novalidate/validate;
745
746 /*修改约束条件，延时验证，commit时验证*/
747 alter table table_name modify constraint constraint_name initially deferred;
748
749 /*修改约束条件，立即验证*/
750 alter table table_name modify constraint constraint_name initially immediate;
751
752 alter session set constraints=deferred/immediate;
753
754 /*drop一个有外键的主键表,带cascade constraints参数级联删除*/
755 drop table table_name cascade constraints;
756
757 /*当truncate外键表时，先将外键设为无效，再truncate;*/
758 truncate table table_name;
759
760 /*设约束条件无效*/
761 alter table table_name disable constraint constraint_name;
762
763 alter table table_name enable novalidate constraint constraint_name;
764
765 /*将无效约束的数据行放入exception的表中，此表记录了违反数据约束的行的行号；在此之前，要先建exceptions表*/
766 alter table table_name add constraint constraint_name check(column_name >15) enable validate exceptions into exceptions;
767
768 /*运行创建exceptions表的脚本*/
769 start $ORACLE_HOME/rdbms/admin/utlexcpt.sql;
770
771 /*获取约束条件信息的表或视图*/
772 select * from user_constraints/dba_constraints/dba_cons_columns;
773
774 ################## managing password security and resources ####################
775
776 alter user user_name account unlock/open;----锁定/打开用户;
777
778 alter user user_name password expire;---设定口令到期
779
780 /*建立口令配置文件,failed_login_attempts口令输多少次后锁，password_lock_times指多少天后口令被自动解锁*/
781 create profile profile_name limit failed_login_attempts 3 password_lock_times 1/1440;
782 /*创建口令配置文件*/
783 create profile profile_name limit failed_login_attempts 3 password_lock_time unlimited password_life_time 30 password_reuse_time 30 password_verify_function verify_function password_grace_time 5;
784 /*建立资源配置文件*/
785 create profile prfile_name limit session_per_user 2 cpu_per_session 10000 idle_time 60 connect_time 480;
786
787 alter user user_name profile profile_name;
788
789 /*设置口令解锁时间*/
790 alter profile profile_name limit password_lock_time 1/24;
791
792 /*password_life_time指口令文件多少时间到期，password_grace_time指在第一次成功登录后到口令到期有多少天时间可改变口令*/
793 alter profile profile_name limit password_lift_time 2 password_grace_time 3;
794
795 /*password_reuse_time指口令在多少天内可被重用,password_reuse_max口令可被重用的最大次数*/
796 alter profile profile_name limit password_reuse_time 10[password_reuse_max 3];
797
798 alter user user_name identified by input_password;-----修改用户口令
799
800 drop profile profile_name;
801
802 /*建立了profile后，且指定给某个用户，则必须用CASCADE才能删除*/
803 drop profile profile_name CASCADE;
804
805 alter system set resource_limit=true;---启用自愿限制,缺省是false
806
807 /*配置资源参数*/
808 alter profile profile_name limit cpu_per_session 10000 connect_time 60 idle_time 5;
809 /*资源参数(session级)
810 cpu_per_session 每个session占用cpu的时间 单位1/100秒
811 sessions_per_user 允许每个用户的并行session数
812 connect_time 允许连接的时间 单位分钟
813 idle_time 连接被空闲多少时间后，被自动断开 单位分钟
814 logical_reads_per_session 读块数
815 private_sga 用户能够在SGA中使用的私有的空间数 单位bytes
816
817 (call级)
818 cpu_per_call 每次(1/100秒)调用cpu的时间
819 logical_reads_per_call 每次调用能够读的块数
820 */
821
822 alter profile profile_name limit cpu_per_call 1000 logical_reads_per_call 10;
823
824 desc dbms_resouce_manager;---资源管理器包
825
826 /*获取资源信息的表或视图*/
827 select * from dba_users/dba_profiles;
828
829 ###### Managing users ############
830
831 show parameter os;
832
833 create user testuser1 identified by kxf_001;
834
835 grant connect,createtable to testuser1;
836
837 alter user testuser1 quota 10m on tablespace_name;
838
839 /*创建用户*/
840 create user user_name identified by password default tablespace tablespace_name temporary tablespace tablespace_name quota 15m on tablespace_name password expire;
841
842 /*数据库级设定缺省临时表空间*/
843 alter database default temporary tablespace tablespace_name;
844
845 /*制定数据库级的缺省表空间*/
846 alter database default tablespace tablespace_name;
847
848 /*创建os级审核的用户，需知道os_authent_prefix，表示oracle和os口令对应的前缀,‘OPS$‘为此参数的值，此值可以任意设置*/
849 create user user_name identified by externally default OPS$tablespace_name tablespace_name temporary tablespace tablespace_name quota 15m on tablespace_name password expire;
850
851 /*修改用户使用表空间的限额,回滚表空间和临时表空间不允许授予限额*/
852 alter user user_name quota 5m on tablespace_name;
853
854 /*删除用户或删除级联用户(用户对象下有对象的要用CASCADE，将其下一些对象一起删除)*/
855 drop user user_name [CASCADE];
856
857 /*每个用户在哪些表空间下有些什么限额*/
858 desc dba_ts_quotas;select * from dba_ts_quotas where username=‘...‘;
859
860 /*改变用户的缺省表空间*/
861 alter user user_name default tablespace tablespace_name;
862
863 ######### Managing Privileges #############
864
865 grant create table,create session to user_name;
866
867 grant create any table to user_name; revoke create any table from user_name;
868
869 /*授予权限语法,public 标识所有用户,with admin option允许能将权限授予第三者的权限*/
870 grant system_privs,[......] to [user/role/public],[....] [with admin option];
871
872 select * from v$pwfile_users;
873
874 /*当 O7_dictionary_accessiblity参数为True时，标识select any table时，包括系统表也能select ,否则，不包含系统表;缺省为false*/
875 show parameter O7;
876
877 /*由于 O7_dictionary_accessiblity为静态参数，不能动态改变，故加scope=spfile,下次启动时才生效*/
878 alter system set O7_dictionary_accessiblity=true scope=spfile;
879
880 /*授予对象中的某些字段的权限，如select 某表中的某些字段的权限*/
881 grant [object_privs(column,....)],[...] on object_name to user/role/public,... with grant option;
882
883 /*oracle不允许授予select某列的权限,但可以授insert ,update某列的权限*/
884 grant insert(column_name1,column_name2,...) on table_name to user_name with grant option;
885
886 select * from dba_sys_privs/session_privs/dba_tab_privs/user_tab_privs/dba_col_privs/user_col_privs;
887
888 /*db/os/none 审计被记录在 数据库/操作系统/不审计 缺省是none*/
889 show parameter audit_trail;
890
891 /*启动对表的select动作*/
892 audit select on user.table_name by session;
893
894 /*by session在每个session中发出command只记录一次，by access则每个command都记录*/
895 audit [create table][select/update/insert on object by session/access][whenever successful/not successful];
896
897 desc dbms_fga;---进一步设计，则可使用dbms_fgs包
898
899 /*取消审计*/
900 noaudit select on user.table_name;
901
902 /*查被审计信息*/
903 select * from all_def_audit_opts/dba_stmt_audit_opts/dba_priv_audit_opts/dba_obj_audit_opts;
904
905 /*获取审计记录*/
906 select * from dba_audit_trail/dba_audit_exists/dba_audit_object/dba_audit_session/dba_audit_statement;
907
908 ########### Managing Role #################
909
910 create role role_name; grant select on table_name to role_name; grant role_name to user_name; set role role_name;
911
912 create role role_name;
913 create role role_name identified by password;
914 create role role_name identified externally;
915
916 set role role_name ; ----激活role
917 set role role_name identified by password;
918
919 alter role role_name not identified;
920 alter role role_name identified by password;
921 alter role role_name identified externally;
922
923 grant priv_name to role_name [WITH ADMIN OPTION];
924 grant update(column_name1,col_name2,...) on table_name to role_name;
925 grant role_name1 to role_name2;
926
927 /*建立default role,用户登录时，缺省激活default role*/
928 alter user user_name default role role_name1,role_name2,...;
929 alter user user_name default role all;
930 alter user user_name default role all except role_name1,...;
931 alter user user_name default role none;
932
933 set role role1 [identified by password],role2,....;
934 set role all;
935 set role except role1,role2,...;
936 set role none;
937
938 revoke role_name from user_name;
939 revoke role_name from public;
940
941 drop role role_name;
942
943 select * from dba_roles/dba_role_privs/role_role_privs/dba_sys_privs/role_sys_privs/role_tab_privs/session_roles;
944
945 ########### Basic SQL SELECT ################
946
947 select col_name as col_alias from table_name ;
948
949 select col_name from table_name where col1 like ‘_o%‘; ----‘_‘匹配单个字符
950
951 /*使用字符函数(右边截取,字段中包含某个字符,左边填充某字符到固定位数,右边填充某字符到固定位数)*/
952 select substr(col1,-3,5),instr(col2,‘g‘),LPAD(col3,10,‘$‘),RPAD(col4,10,‘%‘) from table_name;
953
954 /*使用数字函数(往右/左几位四舍五入,取整,取余)*/
955 select round(col1,-2),trunc(col2),mod(col3) from table_name ;
956
957 /*使用日期函数(计算两个日期间相差几个星期,两个日期间相隔几个月,在某个月份上加几个月,某个日期的下一个日期,
958 某日期所在月的最后的日期,对某个日期的月分四舍五入，对某个日期的月份进行取整)*/
959 select (sysdate-col1)/7 week,months_between(sysdate,col1),add_months(col1,2),next_day(sysdate,‘FRIDAY‘),last_day(sysdate),
960 round(sysdate,‘MONTH‘),trunc(sysdate,‘MONTH‘) from table_name;
961
962 /*使用NULL函数(当expr1为空取expr2/当expr1为空取expr2,否则取expr3/当expr1=expr2返回空)*/
963 select nvl(expr1,expr2),nvl2(expr1,expr2,expr3),nullif(expr1,expr2) from table_name;
964
965 select column1,column2,column3, case column2 when ‘50‘ then column2*1.1
966 when ‘30‘ then column2*2.1
967 when ‘10‘ then column3/20
968 else column3
969 end as ttt
970 from table_name ; ------使用case函数
971
972 select table1.col1,table2.col2 from table1
973 [CROSS JOIN table2] | -----笛卡儿连接
974 [NATURAL JOIN table2] | -----用两个表中的同名列连接
975 [JOIN table2 USING (column_name)] | -----用两个表中的同名列中的某一列或几列连接
976 [JOIN table2
977 ON (table1.col1=table2.col2)] |
978 [LEFT|RIGHT|FULL OUTER JOIN table2 ------相当于(+)=,=(+)连接,全外连接
979 ON (table1.col1=table2.col2)]; ------SQL 1999中的JOIN语法;
980
981 example:
982 select col1,col2 from table1 t1
983 join table2 t2
984 on t1.col1=t2.col2 and t1.col3=t2.col1
985 join table3 t3
986 on t2.col1=t3.col3;
987
988 select * from table_name where col1 < any (select col2 from table_name2 where continue group by col3);
989
990 select * from table_name where col1 < all (select col2 from table_name2 where continue group by col3);
991
992 insert into (select col1,col2,col3 form table_name where col1> 50 with check option) values (value1,value2,value3);
993
994 MERGE INTO table_name table1
995 USING table_name2 table2
996 ON (table1.col1=table2.col2)
997 WHEN MATCHED THEN
998 UPDATE SET
999 table1.col1=table2.col2,
1000 table1.col2=table2.col3,
1001 ...
1002 WHEN NOT MATCHED THEN
1003 INSERT VALUES(table2.col1,table2.col2,table2.col3,...); -----合并语句
1004
1005 ##################### CREATE/ALTER TABLE #######################
1006
1007 alter table table_name drop column column_name ;---drop column
1008
1009 alter table table_name set unused (col1,col2,...);----设置列无效，这个比较快。
1010 alter table table_name drop unused columns;---删除被设为无效的列
1011
1012 rename table_name1 to table_name2; ---重命名表
1013
1014 comment on table table_name is ‘comment message‘;----给表放入注释信息
1015
1016 create table table_name
1017 (col1 int not null,col2 varchar2(20),col3 varchar2(20),
1018 constraint uk_test2_1 unique(col2,col3))); -----定义表中的约束条件
1019
1020 alter table table_name add constraint pk_test2 primary key(col1,col2,...); ----创建主键
1021
1022 /*建立外键*/
1023 create table table_name (rid int,name varchar2(20),constraint fk_test3 foreign key(rid) references other_table_name(id));
1024
1025 alter table table_name add constraint ck_test3 check(name like ‘K%‘);
1026
1027 alter table table_name drop constraint constraint_name;
1028
1029 alter table table_name drop primary key cascade;----级联删除主键
1030
1031 alter table table_name disable/enable constraint constraint_name;----使约束暂时无效
1032
1033 /*删除列，并级联删除此列下的约束条件*/
1034 alter table table_name drop column column_name cascade constraint;
1035
1036 select * from user_constraints/user_cons_columns;---约束条件相关视图
1037
1038 ############## Create Views #####################
1039
1040 CREATE [OR REPLACE] [FORCE|NOFORCE] VIEW view_name [(alias[,alias]...)]
1041 AS subquery
1042 [WITH CHECK OPTION [CONSTRAINT constraint_name]]
1043 [WITH READ ONLY [CONSTRAINT constraint_name]]; ------创建视图的语法
1044
1045 example: Create or replace view testview as select col1,col2,col3 from table_name; ------创建视图
1046 /*使用别名*/
1047 Create or replace view testview as select col1,sum(col2) col2_alias from table_name;
1048 /*创建复杂视图*/
1049 Create view view_name (alias1,alias2,alias3,alias4) as select d.col1,min(e.col1),max(e.col1),avg(e.col1) from table_name1 e,table_name2 d where e.col2=d.col2 group by d.col1;
1050 /*当用update修改数据时，必须满足视图的col1>10的条件，不满足则不能被改变.*/
1051 Create or replace view view_name as select * from table_name where col1>10 with check option;
1052
1053 /*改变视图的值.对于简单视图可以用update语法修改表数据，但复杂视图则不一定能改。如使用了函数，group by ,distinct等的列*/
1054 update view_name set col1=value1;
1055
1056 /*TOP-N分析*/
1057 select [column_list],rownum from (select [column_list] from table_name order by Top-N_column) where rownum<=N;
1058
1059 /*找出某列三条最大值的记录*/
1060 example: select rownum as rank ,col1 ,col2 from (select col1 ,col2 from table_name order by col2 desc) where rownum<=3;
1061
1062 ############# Other database Object ###############
1063
1064 CREATE SEQUENCE sequence_name [INCREMENT BY n]
1065 [START WITH n]
1066 [{MAXVALUE n | NOMAXVALUE}]
1067 [{MINVALUE n | NOMINVALUE}]
1068 [{CYCEL | NOCYCLE}]
1069 [{CACHE n | NOCACHE}]; -----创建SEQUENCE
1070
1071 example:
1072 CREATE SEQUENCE sequence_name INCREMENT BY 10
1073 START WITH 120
1074 MAXVALUE 9999
1075 NOCACHE
1076 NOCYCLE;
1077
1078 select * from user_sequences ;---当前用户下记录sequence的视图
1079
1080 select sequence_name.nextval,sequence_name.currval from dual;-----sequence的引用
1081
1082 alter sequence sequence_name INCREMENT BY 20
1083 MAXVALUE 999999
1084 NOCACHE
1085 NOCYCLE; -----修改sequence,不能改变起始序号
1086
1087 drop sequence sequence_name; ----删除sequence
1088
1089 CREATE [PUBLIC] SYNONYM synonym_name FOR object; ------创建同义词
1090
1091 DROP [PUBLIC] SYNONYM synonym_name;----删除同义词
1092
1093 CREATE PUBLIC DATABASE LINK link_name USEING OBJECT;----创建DBLINK
1094
1095 select * from object_name@link_name; ----访问远程数据库中的对象
1096
1097 /*union 操作，它将两个集合的交集部分压缩，并对数据排序*/
1098 select col1,col2,col3 from table1_name union select col1,col2,col3 from table2_name;
1099
1100 /*union all 操作，两个集合的交集部分不压缩，且不对数据排序*/
1101 select col1,col2,col3 from table1_name union all select col1,col2,col3 from table2_name;
1102
1103 /*intersect 操作，求两个集合的交集,它将对重复数据进行压缩，且排序*/
1104 select col1,col2,col3 from table1_name intersect select col1,col2,col3 from table2_name;
1105
1106 /*minus 操作，集合减,它将压缩两个集合减后的重复记录, 且对数据排序*/
1107 select col1,col2,col3 from table1_name minus select col1,col2,col3 from table2_name;
1108
1109 /*EXTRACT 抽取时间函数. 此例是抽取当前日期中的年*/
1110 select EXTRACT(YEAR FROM SYSDATE) from dual;
1111 /*EXTRACT 抽取时间函数. 此例是抽取当前日期中的月*/
1112 select EXTRACT(MONTH FROM SYSDATE) from dual;
1113
1114 ########################## 增强的 group by 子句 #########################
1115
1116 select [column,] group_function(column)...
1117 from table
1118 [WHERE condition]
1119 [GROUP BY [ROLLUP] group_by_expression]
1120 [HAVING having_expression];
1121 [ORDER BY column]; -------ROLLUP操作字，对group by子句的各字段从右到左进行再聚合
1122
1123 example:
1124 /*其结果看起来象对col1做小计*/
1125 select col1,col2,sum(col3) from table group by rollup(col1,col2);
1126 /*复合rollup表达式*/
1127 select col1,col2,sum(col3) from table group by rollup((col1,col2));
1128
1129 select [column,] group_function(column)...
1130 from table
1131 [WHERE condition]
1132 [GROUP BY [CUBE] group_by_expression]
1133 [HAVING having_expression];
1134 [ORDER BY column]; -------CUBE操作字，除完成ROLLUP的功能外，再对ROLLUP后的结果集从右到左再聚合
1135
1136 example:
1137 /*其结果看起来象对col1做小计后，再对col2做小计，最后算总计*/
1138 select col1,col2,sum(col3) from table group by cube(col1,col2);
1139 /*复合rollup表达式*/
1140 select col1,col2,sum(col3) from table group by cube((col1,col2));
1141 /*混合rollup,cube表达式*/
1142 select col1,col2,col3,sum(col4) from table group by col1,rollup(col2),cube(col3);
1143
1144 /*GROUPING(expr)函数，查看select语句种以何字段聚合，其取值为0或1*/
1145 select [column,] group_function(column)...,GROUPING(expr)
1146 from table
1147 [WHERE condition]
1148 [GROUP BY [ROLLUP] group_by_expression]
1149 [HAVING having_expression];
1150 [ORDER BY column];
1151
1152 example:
1153 select col1,col2,sum(col3),grouping(col1),grouping(col2) from table group by cube(col1,col2);
1154
1155 /*grouping sets操作，对group by结果集先对col1求和，再对col2求和，最后将其结果集并在一起*/
1156 select col1,col2,sum(col3) from table group by grouping sets((col1),(col2));
时间： 2024-10-18 20:10:25