在Oracle pl/sql电子邮件发送中运行For循环时如何使用变量作为表名

Question

我无法编译Oracle代码的这一部分,因为编译器报告"PL/SQL:ORA-00942:表或视图不存在"

Oracle表存在,但此过程必须根据"Order_ID"参数将表名传递给For循环过程.我在表存在的Schema中工作,所以我没有解决模式名称.

示例:TEMP_TBL_123存在于数据库中,通过传递order_ID为123,我尝试使用变量TMP_TBL_NM来保存表名"TEMP_TBL_123".

.................................................

CREATE OR REPLACE PROCEDURE EMAIL_DEPT_BLAST_TEST (SUBJECT VARCHAR2,MAIL_FROM VARCHAR2, MAIL_TO VARCHAR2,
                                               L_MESSAGE VARCHAR2, L_MESSAGE2 VARCHAR2, ORDER_ID NUMBER)
IS
MAIL_HOST VARCHAR2(30):='XX.XX.XX.XX';
MAIL_CONN UTL_SMTP.CONNECTION;
TMP_TBL_NM VARCHAR2(30);

BEGIN

TMP_TBL_NM := 'TEMP_TBL_' || ORDER_ID;

MAIL_CONN := UTL_SMTP.OPEN_CONNECTION(MAIL_HOST, 25);
UTL_SMTP.HELO(MAIL_CONN, MAIL_HOST);
UTL_SMTP.MAIL(MAIL_CONN,'XXX@XXXXXX.com');
UTL_SMTP.RCPT(MAIL_CONN, MAIL_TO);
UTL_SMTP.OPEN_DATA(MAIL_CONN);
UTL_SMTP.WRITE_DATA(MAIL_CONN, 'Date: '||to_char(trunc(SYSDATE))||utl_tcp.crlf);
UTL_SMTP.WRITE_DATA(MAIL_CONN, 'From: '|| mail_from ||utl_tcp.crlf);
UTL_SMTP.WRITE_DATA(MAIL_CONN, 'To: '|| mail_to || utl_tcp.crlf);
UTL_SMTP.WRITE_DATA(MAIL_CONN, 'Subject: '||subject||utl_tcp.crlf);
UTL_SMTP.WRITE_DATA(MAIL_CONN, UTL_TCP.CRLF);
UTL_SMTP.WRITE_DATA(MAIL_CONN, ''|| L_MESSAGE || UTL_TCP.CRLF);
UTL_SMTP.WRITE_DATA(MAIL_CONN, UTL_TCP.CRLF);

UTL_SMTP.WRITE_DATA(MAIL_CONN, 'Order details:' || UTL_TCP.crlf);
UTL_SMTP.WRITE_DATA(MAIL_CONN, 'Quantity - Location ID - Address' || UTL_TCP.crlf);

BEGIN
    FOR I IN (SELECT LOCATION_ID, TRIM(TO_CHAR(COUNT(*),'9,999')) AS QUANTITY FROM TMP_TBL_NM GROUP BY LOCATION_ID)
    LOOP 
    UTL_SMTP.WRITE_DATA(MAIL_CONN, I.QUANTITY  || ' - ');
    UTL_SMTP.WRITE_DATA(MAIL_CONN, I.LOCATION_ID || ' ');
    UTL_SMTP.WRITE_DATA(MAIL_CONN,UTL_TCP.CRLF);
    END LOOP;
END;

UTL_SMTP.WRITE_DATA(MAIL_CONN, L_MESSAGE2 || UTL_TCP.CRLF);  

UTL_SMTP.WRITE_DATA(MAIL_CONN,UTL_TCP.CRLF);
UTL_SMTP.CLOSE_DATA(MAIL_CONN);
UTL_SMTP.QUIT(MAIL_CONN);

END SCT_CNTS_EMAIL_DEPT_BLAST_TEST;

Answer 1

我没有太多运气让约翰的榜样奏效.这是做的事情:

DECLARE
    C SYS_REFCURSOR;
    stmt VARCHAR2(1000); 
    tmp_tbl_nm  VARCHAR2(64) := 'USER_TABLES';
    the_name    VARCHAR2(64);
BEGIN
    stmt := 'SELECT table_name  FROM ' || TMP_TBL_NM || ' ORDER BY 1';
    OPEN C FOR stmt;
    LOOP
      FETCH C INTO the_name;
      EXIT WHEN C%NOTFOUND;
      dbms_output.put_line(the_name);
    END LOOP;
END;
/
CONTINENT
COUNTRY
COUNTRYINFOIMPORT
COUNTRY_LANGUAGE
GEONAME
LANGUAGE

PL/SQL procedure successfully completed.

SQL>

我不认为你可以使用EXECUTE IMMEDIATE语句返回游标.这个文档页面,第二段似乎表明没有.无论如何,你不需要它,只需使用OPEN - FOR语法.

Answer 2

像这样将变量传递到 SQL 语句的唯一方法是将查询作为动态 sql运行。

您的代码可能类似于：

DECLARE
    query_output SYS_REFCURSOR;
    query_statement VARCHAR2(1000); 
BEGIN
    query_statement := 'SELECT LOCATION_ID, TRIM(TO_CHAR(COUNT(*),'9,999')) AS QUANTITY FROM ' || TMP_TBL_NM || ' GROUP BY LOCATION_ID';
    execute immediate query_statement using out query_output;
    ....
END

现在您有了光标，获取内容，循环计数并执行其他所有操作