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???????????? ???????[ 2013/3/11 11:17:32 ] ????????

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SQL> create or replace procedure sql_explain(v_sql varchar2)
2 is
3 type explain_cursor_type is ref cursor;
4 explain_cursor explain_cursor_type;
5 a varchar2(2048);
6 begin
7    execute immediate 'explain plan for '||v_sql;
8    open explain_cursor for select PLAN_TABLE_OUTPUT from table(dbms_xplan.display());
9    loop
10      fetch explain_cursor into a;
11      exit when explain_cursor%NOTFOUND;
12     dbms_output.put_line(a);
13    end loop;
14 end;
15 /

Procedure created.
SQL> exec sql_explain('select a.name??b.name from t1 a??t2 b where a.id=b.id and a.id=1');
Plan hash value: 2680223496
--------------------------------------------------------------------------------------
| Id | Operation                    | Name | Rows | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT             |       |     1 |    17 |     4   (0)| 00:00:01 |
|   1 | NESTED LOOPS                |       |     1 |    17 |     4   (0)| 00:00:01 |
|   2 |   TABLE ACCESS BY INDEX ROWID| T1    |     1 |     8 |     1   (0)| 00:00:01 |
|* 3 |    INDEX UNIQUE SCAN         | T1_PK |     1 |       |     0   (0)| 00:00:01 |
|* 4 |   TABLE ACCESS FULL          | T2    |     1 |     9 |     3   (0)| 00:00:01 |
--------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
3 - access("A"."ID"=1)
4 - filter("B"."ID"=1)

PL/SQL procedure successfully completed.

SQL> exec sql_explain('select a.name??b.name from t1 a??t2 b where a.id=b.id and a.id=''1''');
Plan hash value: 2680223496
--------------------------------------------------------------------------------------
| Id | Operation                    | Name | Rows | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT             |       |     1 |    17 |     4   (0)| 00:00:01 |
|   1 | NESTED LOOPS                |       |     1 |    17 |     4   (0)| 00:00:01 |
|   2 |   TABLE ACCESS BY INDEX ROWID| T1    |     1 |     8 |     1   (0)| 00:00:01 |
|* 3 |    INDEX UNIQUE SCAN         | T1_PK |     1 |       |     0   (0)| 00:00:01 |
|* 4 |   TABLE ACCESS FULL          | T2    |     1 |     9 |     3   (0)| 00:00:01 |
--------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
3 - access("A"."ID"=1)
4 - filter("B"."ID"=1)

PL/SQL procedure successfully completed.

?????????????format????????????

SQL> create or replace procedure sql_explain(v_sql varchar2??v_format varchar2)
2 is
3 type explain_cursor_type is ref cursor;
4 explain_cursor explain_cursor_type;
5 a varchar2(2048);
6 begin
7    execute immediate 'explain plan for '||v_sql;
8    open explain_cursor for select PLAN_TABLE_OUTPUT from table(dbms_xplan.display(null??null??v_format));
9    loop
10      fetch explain_cursor into a;
11      exit when explain_cursor%NOTFOUND;
12     dbms_output.put_line(a);
13    end loop;
14 end;
15 /

Procedure created.
SQL> exec sql_explain('select a.name??b.name from t1 a??t2 b where a.id=b.id and a.id=1'??'all');
Plan hash value: 2680223496
--------------------------------------------------------------------------------------
| Id | Operation                    | Name | Rows | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT             |       |     1 |    17 |     4   (0)| 00:00:01 |
|   1 | NESTED LOOPS                |       |     1 |    17 |     4   (0)| 00:00:01 |
|   2 |   TABLE ACCESS BY INDEX ROWID| T1    |     1 |     8 |     1   (0)| 00:00:01 |
|* 3 |    INDEX UNIQUE SCAN         | T1_PK |     1 |       |     0   (0)| 00:00:01 |
|* 4 |   TABLE ACCESS FULL          | T2    |     1 |     9 |     3   (0)| 00:00:01 |
--------------------------------------------------------------------------------------
Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------
1 - SEL$1
2 - SEL$1 /A@SEL$1
3 - SEL$1 /A@SEL$1
4 - SEL$1 /B@SEL$1
Predicate Information (identified by operation id):
---------------------------------------------------
3 - access("A"."ID"=1)
4 - filter("B"."ID"=1)
Column Projection Information (identified by operation id):
-----------------------------------------------------------
1 - (#keys=0) "A"."NAME"[VARCHAR2??32]?? "B"."NAME"[VARCHAR2??32]
2 - "A"."NAME"[VARCHAR2??32]
3 - "A".ROWID[ROWID??10]
4 - "B"."NAME"[VARCHAR2??32]