Question

我正在尝试对Emp表，创建表和＆amp;插入的行如下所示。我正在尝试开发一个存储过程，它将获取来自oracle ALL_TAB_COLUMNS＆amp;的特定表的所有列。我将生成统计数据。

下面给出的PL / SQL代码块正在编译但在运行时没有返回任何记录。谁能告诉我可能出错的地方 -

`is "distinct_cnt := 'SELECT COUNT(DISTINCT (' || table_rec.COLUMN_NAME || ')) FROM' || table_rec.TABLE_NAME;"`

将结果分配给变量的正确方法。

create table emp( empno  number(4,0),
ename    varchar2(10),
job      varchar2(9),
mgr      number(4,0), 
hiredate date, 
sal      number(7,2),
comm     number(7,2), 
deptno   number(2,0)
)

insert into emp values( 7839, 'KING', 'PRESIDENT', null, to_date('17-11-1981','dd-mm-yyyy'), 5000, null, 10);
insert into emp values( 7698, 'BLAKE', 'MANAGER', 7839, to_date('1-5-1981','dd-mm-yyyy'), 2850, null, 30);
insert into emp values( 7782, 'CLARK', 'MANAGER', 7839, to_date('9-6-1981','dd-mm-yyyy'), 2450, null, 10);
insert into emp values( 7566, 'JONES', 'MANAGER', 7839, to_date('2-4-1981','dd-mm-yyyy'), 2975, null, 20);
insert into emp values( 7788, 'SCOTT', 'ANALYST', 7566, to_date('13-JUL-87','dd-mm-rr') - 85, 3000, null, 20);
insert into emp values( 7902, 'FORD', 'ANALYST', 7566, to_date('3-12-1981','dd-mm-yyyy'), 3000, null, 20);
insert into emp values( 7369, 'SMITH', 'CLERK', 7902, to_date('17-12-1980','dd-mm-yyyy'), 800, null, 20);
insert into emp values( 7499, 'ALLEN', 'SALESMAN', 7698, to_date('20-2-1981','dd-mm-yyyy'), 1600, 300, 30);
insert into emp values( 7521, 'WARD', 'SALESMAN', 7698, to_date('22-2-1981','dd-mm-yyyy'), 1250, 500, 30);
insert into emp values( 7654, 'MARTIN', 'SALESMAN', 7698, to_date('28-9-1981','dd-mm-yyyy'), 1250, 1400, 30);
insert into emp values( 7844, 'TURNER', 'SALESMAN', 7698, to_date('8-9-1981','dd-mm-yyyy'), 1500, 0, 30);
insert into emp values( 7876, 'ADAMS', 'CLERK', 7788, to_date('13-JUL-87', 'dd-mm-rr') - 51, 1100, null, 20);
insert into emp values( 7900, 'JAMES', 'CLERK', 7698, to_date('3-12-1981','dd-mm-yyyy'), 950, null, 30);
insert into emp values( 7934, 'MILLER', 'CLERK', 7782, to_date('23-1-1982','dd-mm-yyyy'), 1300, null, 10);

 Commit;


create or replace
procedure p_profiling (V_tablename IN varchar2)
IS

cursor c1 is
select TABLE_NAME,
COLUMN_NAME
from
ALL_TAB_COLUMNS
where TABLE_NAME='V_tablename';


REC_CNT NUMBER;
distinct_cnt NUMBER;
is_valid NUMBER;
not_null NUMBER;

BEGIN

FOR table_rec in c1
LOOP

REC_CNT := 'SELECT COUNT(*) FROM' ||  table_rec.TABLE_NAME;

distinct_cnt := 'SELECT COUNT(DISTINCT (' || table_rec.COLUMN_NAME || ')) FROM' || table_rec.TABLE_NAME;

is_valid := 'SELECT COUNT(*) FROM '||table_rec.TABLE_NAME ||'WHERE'|| table_rec.COLUMN_NAME ||' IS NOT NULL
            AND LENGTH('||table_rec.COLUMN_NAME||') = LENGTH(LTRIM(RTRIM('||table_rec.COLUMN_NAME||')))';

not_null := 'SELECT COUNT(*)  FROM'|| table_rec.TABLE_NAME ||'WHERE '|| table_rec.COLUMN_NAME ||'IS NOT NULL';

DBMS_OUTPUT.PUT_LINE ('REC_CNT:'||REC_CNT||' '||'distinct_cnt:'||distinct_cnt||' '||'is_valid:'||is_valid ||'  '||'TABLE_NAME'||table_rec.TABLE_NAME||' '||'COLUMN_NAME'||table_rec.COLUMN_NAME);

END LOOP;

END;

Answer 1

您需要使用EXECUTE IMMEDIATE来执行这些动态查询，以获取您要查找的数据。

查看此帖子：dynamic SELECT INTO clause in PL/SQL

希望得到这个帮助。

Answer 2

为了执行动态创建的SQL语句，您需要使用EXECUTE IMMEDIATE：

create or replace
procedure p_profiling (V_tablename IN varchar2)
IS

cursor c1 is 
select TABLE_NAME,
COLUMN_NAME
from
ALL_TAB_COLUMNS
where TABLE_NAME='V_tablename';


REC_CNT NUMBER;
distinct_cnt NUMBER;
is_valid NUMBER;
not_null NUMBER;


BEGIN

FOR table_rec in c1

LOOP

IF c1%ROWCOUNT = 1 THEN 

EXECUTE IMMEDIATE  'SELECT COUNT(*) FROM' ||  
table_rec.TABLE_NAME INTO  REC_CNT;

END IF;

EXECUTE IMMEDIATE  'SELECT COUNT(DISTINCT (' || 
table_rec.COLUMN_NAME || ')) FROM' || 
table_rec.TABLE_NAME INTO distinct_cnt;

EXECUTE IMMEDIATE 'SELECT COUNT(*) FROM '||
table_rec.TABLE_NAME ||'WHERE'|| table_rec.COLUMN_NAME ||' 
IS NOT NULL
AND LENGTH('||table_rec.COLUMN_NAME||') = 
LENGTH(LTRIM(RTRIM  ('||table_rec.COLUMN_NAME||')))' INTO is_valid;

EXECUTE IMMEDIATE  'SELECT COUNT(*)  FROM'|| 
table_rec.TABLE_NAME ||'WHERE '|| table_rec.COLUMN_NAME 
||'IS NOT NULL' INTO not_null;


DBMS_OUTPUT.PUT_LINE('REC_CNT:'||REC_CNT||' '||'distinct_cnt:'||
distinct_cnt||' '
||'is_valid:'||is_valid   ||'  '||'TABLE_NAME'||table_rec.TABLE_NAME||' '
||'COLUMN_NAME'||table_rec.COLUMN_NAME);

END LOOP;

END;

PL / SQL使用游标列为变量赋值

2 个答案: