Oracle中锁定行的查找方法

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