oracle plsql將一個變量連接到一個字符串

Question

下面是當程序運行時通過給P_LOC賦值爲'DALLAS' 它給出的錯誤爲-904 ORA-00904：「DALLAS」：請使用無效標識符提供一種解決方案

create or replace 
PROCEDURE PR_EMP_LST1 
(P_LOC IN VARCHAR2 
, P_MIN_SAL IN NUMBER 
, P_MAX_SAL IN NUMBER 
, P_REF_CUR OUT SYS_REFCURSOR 
) AS 

    TYPE TY_LST_REFCURSOR IS REF CURSOR ; 
    cur_emp_lst TY_LST_REFCURSOR; 
    v_inv_query VARCHAR2(2000); 
    V_USG_CL VARCHAR2(200); 


BEGIN 

    IF P_LOC IS NULL AND p_min_sal IS NULL AND p_max_sal IS NULL THEN 
     v_inv_query :='SELECT ENAME 
        FROM EMP '; 
    ELSE    
     v_inv_query :='SELECT ENAME 
        FROM EMP WHERE '; 


    IF P_LOC IS NULL AND p_min_sal IS NOT NULL AND p_max_sal IS NOT NULL THEN     

     v_inv_query :=v_inv_query ||' SAL BETWEEN ' 
            ||p_min_sal 
            ||' AND ' 
            || p_max_sal; 
     -- v_inv_query :=v_inv_query ||' SAL BETWEEN :1 AND :2 '; 

      dbms_output.put_line('2'); 
    -- V_USG_CL:= ' USING '||p_min_sal||' , '|| p_max_sal; 
    ELSIF P_LOC IS NOT NULL AND p_min_sal IS NOT NULL AND p_max_sal IS NOT NULL THEN 
    dbms_output.put_line('1'); 
     v_inv_query :=v_inv_query||' SAL BETWEEN ' 
            ||p_min_sal || ' AND '|| p_max_sal 
            || ' AND DEPTNO IN (SELECT DEPTNO 
               FROM DEPT 
               WHERE LOC= ' 
               || p_loc 
               ||')'; 
      dbms_output.put_line('2');          
    ELSIF P_LOC IS NOT NULL AND p_min_sal IS NULL AND p_max_sal IS NOT NULL THEN  
     v_inv_query :=v_inv_query||' SAL <= ' 
            ||p_max_sal 
            ||' AND DEPTNO IN (SELECT DEPTNO 
               FROM DEPT 
               WHERE LOC= ' 
                || p_loc 
                ||')'; 
     ELSIF P_LOC IS NOT NULL AND p_min_sal IS NOT NULL AND p_max_sal IS NULL THEN 
     v_inv_query :=v_inv_query||' SAL >= ' 
            ||p_min_sal 
            ||' AND DEPTNO IN (SELECT DEPTNO 
                FROM DEPT 
                WHERE LOC= ' 
                ||p_loc 
                ||')'; 
    ELSIF P_LOC IS NULL AND p_min_sal IS NULL AND p_max_sal IS NOT NULL THEN 
     v_inv_query :=v_inv_query||' SAL <= ' 
               ||p_max_sal; 

    ELSIF P_LOC IS NULL AND p_min_sal IS NOT NULL AND p_max_sal IS NULL THEN 
     v_inv_query :=v_inv_query||' SAL >= ' 
            || p_min_sal; 

    ELSIF P_LOC IS NOT NULL AND p_min_sal IS NULL AND p_max_sal IS NULL THEN 
     v_inv_query :=v_inv_query||' DEPTNO IN (SELECT DEPTNO 
                FROM DEPT 
                WHERE LOC= ' 
                ||p_loc 
                ||')';        
    END IF; 
    END IF; 
    dbms_output.put_line('3'); 
    dbms_output.put_line(v_inv_query); 
    OPEN cur_emp_lst FOR v_inv_query ; 

    dbms_output.put_line('4'); 
    P_REF_CUR:=cur_emp_lst;        

END PR_EMP_LST1; 

Answer 1

'SELECT DEPTNO FROM DEPT WHERE LOC = ''' || p_loc ||' '''）';

由於達拉斯是字符串，你需要將它作爲字符串處理：'DALLAS'而不是DALLAS。 '你必須使用''