PLS-00103：遇到符号“，”

Question

此过程出现以下错误。

CREATE OR REPLACE PROCEDURE SAMPLE
IS
BEGIN
EXECUTE IMMEDIATE
    'CREATE TABLE COLUMN_NAMES AS (
     SELECT LISTAGG(COLUMN_NAME, ',') WITHIN GROUP (ORDER BY COLUMN_NAME) AS STUDENTS
     FROM   
         (SELECT DISTINCT COLUMN_NAME
          FROM BW_COLUMN_ROW_CELL_JOIN)
     )';
END;
/

给予：

PLS-00103: Encountered the symbol "," when expecting one of the following:     
* & = - + ; < / > at in is mod remainder not rem return    
returning <an exponent (**)> <> or != or ~= >= <= <> and or   
like like2 like4 likec between into using || multiset bulk    member submultiset 

谁能说说这有什么问题？

谢谢。

Answer 1

另一种方法（在 Oracle 10g 及更高版本中）是使用替代字符串文字表示法 - 这意味着您无需担心正确转义字符串中的所有单引号，例如q'{my string's got embedded quotes}':

CREATE OR REPLACE PROCEDURE SAMPLE
IS
BEGIN
EXECUTE IMMEDIATE q'[
     CREATE TABLE COLUMN_NAMES AS (
     SELECT LISTAGG(COLUMN_NAME, ',') WITHIN GROUP (ORDER BY COLUMN_NAME) AS STUDENTS
     FROM   
         (SELECT DISTINCT COLUMN_NAME
          FROM BW_COLUMN_ROW_CELL_JOIN)
     )]';
END;
/

Answer 2

我认为问题是单引号中有单引号。我目前无法对此进行测试，但我建议您尝试以下方法（注意内引号是双引号 ''，它会转义它们：

CREATE OR REPLACE PROCEDURE SAMPLE 
IS
BEGIN 
    EXECUTE IMMEDIATE 'CREATE TABLE COLUMN_NAMES AS ( SELECT LISTAGG(COLUMN_NAME, '','') WITHIN GROUP (ORDER BY COLUMN_NAME) AS STUDENTS FROM (SELECT DISTINCT COLUMN_NAME FROM BW_COLUMN_ROW_CELL_JOIN) )'; 
END; 
/

我还会先尝试独立代码的create table 部分，以确保它在将其包装到 proc 之前有效。

Answer 3

不能在select statement 的Execute Immediate 中直接使用single quotes，需要使用CHR(39) 编码

CREATE OR REPLACE PROCEDURE SAMPLE
IS
BEGIN
   EXECUTE IMMEDIATE
     'CREATE TABLE COLUMN_NAMES AS (
             SELECT LISTAGG(COLUMN_NAME,'||chr(39)||','||chr(39)||') WITHIN GROUP (ORDER BY COLUMN_NAME) AS STUDENTS
             FROM   
            (SELECT DISTINCT COLUMN_NAME FROM BW_COLUMN_ROW_CELL_JOIN))';
END;