Oracle中锁定行的查找方法

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锁定行的查找

要查找session锁定的行，可以有两种方式：
1. 通过v$session中的row_wait_row#查询

set serverout on size 1000000 set lines 132 declare cursor cur_lock is select sid,id1,id2,inst_id, ctime from gv$lock where block = 1; vid1 number; vid2 number; cursor cur_locked is select sid, inst_id, ctime from gv$lock where id1 = vid1 and id2 = vid2 and block <> 1; vlocks varchar2(30); vsid1 number; vobj1 number; vfil1 number; vblo1 number; vrow1 number; vrowid1 varchar2(20); vcli1 varchar2(64); vobj2 number; vfil2 number; vblo2 number; vrow2 number; vrowid2 varchar2(20); vcli2 varchar2(64); vobjname varchar2(30); vlocked varchar2(30); ctim1 number; ctim2 number; begin dbms_output.put_line('====================================================='); dbms_output.put_line('Blocking lock list.'); dbms_output.put_line('====================================================='); dbms_output.put_line('Block / Is blocked SID INST_ID OBJECT TIME(secs) ROWID CLIENT_IDENTIFIER'); dbms_output.put_line('------------------------- --------- ------- ------------------------------ ---------- ------------------ -----------------'); for c1 in cur_lock loop vid1 := c1.id1; vid2 := c1.id2; select username,sid,row_wait_obj#,row_wait_file#,row_wait_block#,row_wait_row#,client_identifier into vlocks,vsid1,vobj1,vfil1,vblo1,vrow1,vcli1 from gv$session where sid = c1.sid and inst_id = c1.inst_id; if vobj1 = -1 then vobjname := 'UNKNOWN'; else select name into vobjname from sys.obj$ where obj# = vobj1; select decode(vrow1,0,'MANY ROWS',dbms_rowid.rowid_create(1, vobj1, vfil1, vblo1, vrow1)) into vrowid1 from dual; end if; dbms_output.put_line(rpad(vlocks,25) || ' ' || to_char(vsid1,'999999999') || ' ' || to_char(c1.inst_id,'9999999') || ' ' || rpad(vobjname,30) || ' ' || to_char(c1.ctime,'999999999') || ' ' || rpad(vrowid1,18) || ' ' || vcli1); for c2 in cur_locked loop select username, row_wait_obj#,row_wait_file#,row_wait_block#,row_wait_row# into vlocked, vobj2, vfil2, vblo2, vrow2 from gv$session where sid = c2.sid and inst_id = c2.inst_id; if vobj2 = -1 then vobjname := 'UNKNOWN'; else select name into vobjname from sys.obj$ where obj# = vobj2; select decode(vrow2,0,'MANY ROWS',dbms_rowid.rowid_create(1, vobj2, vfil2, vblo2, vrow2)) into vrowid2 from dual; end if; dbms_output.put_line(chr(9) || '--> ' || rpad(vlocked,12) || ' ' || to_char(c2.sid,'999999999') || ' ' || to_char(c2.inst_id,'9999999') || ' ' || rpad(vobjname,30) || ' ' || to_char(c2.ctime,'999999999') || ' ' || rpad(vrowid2,18) || ' ' || vcli2 ) ; end loop; end loop; commit; end;

这种查询方式的局限是只能查询出来一行，如果是多行，则row_wait_row#返回的是锁定的开始行。

2. 通过for update查询所有加锁行

create or replace procedure locksmith(table_name varchar2) is type tabcurtype is ref cursor; type tabrowstype is table of varchar2(50) index by binary_integer; table_cursor tabcurtype; rowid_table tabrowstype; row_id rowid; status number; aud_sid number; test_sid number; test_serial number; locker_sid number; locker_name varchar2(1000); message varchar2(1000); resource_busy exception; pragma exception_init(resource_busy, -54); begin rowid_table(0) := '0'; dbms_output.enable(1000000); open table_cursor for 'select rowid from ' || table_name; loop begin fetch table_cursor into row_id; exit when table_cursor%notfound; savepoint one_register; execute immediate 'select 1 from ' || table_name || ' where rowid =:r for update nowait' using row_id; exception when resource_busy then rowid_table(rowid_table.last + 1) := row_id; end; rollback to savepoint one_register; end loop; close table_cursor; for r in rowid_table.first + 1 .. rowid_table.last loop dbms_output.put_line(rowid_table(r)); end loop; rollback; end;

使用nowait在表中循环所有记录，判断出所有加锁的行。

SQL> exec locksmith('TEST'); AAAM1tAAEAAAANWAAB AAAM1tAAEAAAANWAAC PL/SQL procedure successfully completed