DB2 CTAS令牌错误

Question

我想在DB2版本11.1.0中使用CTAS语句，它创建一个新表并插入它。查询如下：

 CREATE TABLE MY_SCRATCH.LC$U7OB81478732948714_zero_to_3 AS (
     WITH two AS (SELECT id AS the_num FROM users WHERE id = 2) 
     , one_two AS (
     SELECT id AS the_num FROM users WHERE id = 1 
     UNION ALL 
     SELECT * FROM two tmp 
    ) 
     , zero_one_two AS (
     SELECT id-7 AS the_num FROM users where id = 7 
     UNION ALL 
     SELECT * FROM one_two tmp 

    ) 
     SELECT * FROM zero_one_two tmp 
     UNION ALL 
     SELECT id AS the_num FROM users WHERE id = 3 
    ) WITH DATA 

不过，我收到以下错误：

"my_error":"SQL Error: derived_table zero_to_3 creation failed: SQL Error in CREATE TABLE as SELECT: com.ibm.db2.jcc.am.SqlSyntaxErrorException: DB2 SQL Error: SQLCODE=-104, SQLSTATE=42601, SQLERRMC=AS;RO_TO_3\" (\nWITH TWO;JOIN, DRIVER=4.16.53"

据DB2 docs，错误是因为以下几点：

A syntax error was detected where the symbol "token" occurs in the SQL statement. The list of symbols that might be legal shows some alternate symbols that could possibly be correct at that point, if the preceding part of the statement is entirely correct.

所以我在RazorSQL中运行上述查询，并且抛出了相同的错误。不太确定令牌问题的位置是

Answer 1

您不能使用公用表表达式。如果你看一下语法CREATE TABLE（下图删节为您的具体问题）：

>>-CREATE TABLE--table-name-------------------------------------> 

>--+-----------------------+--AS--(--fullselect--)--------------> 
    | .-,-----------. |       
    | V    | |       
    '-(----column-name-+--)-'       

>--+-WITH NO DATA-+---------------------------------------------| 
    '-WITH DATA----' 

一个fullselect是一个充满选择查询的一部分，但它不包括公共表表达式。公用表表达式是select-statement的一部分。

使用嵌套表表达式而不是通用表表达式重写您的查询是可能的，但是对于您的示例查询，如果您甚至根本不需要公用表表达式，则很难说明这一点。您的查询可以用更简单的方式写成：

CREATE TABLE MY_SCRATCH.LC$U7OB81478732948714_zero_to_3 AS (
    select id as the_num from users where id = 2 
    union all 
    select id as the_num from users where id = 1 
    union all 
    select id-7 as the_num from users where id = 7 
    union all 
    select id as the_num from users where id = 3 
) 
    WITH DATA;