Question

我有这样的查询

SELECT "SOME FIELDS"
FROM (SELECT "SOME FIELDS" FROM WHERE FIELD=VALUE1 AND FIELD=VALUE2)
CONNECT BY **PRIOR** FIELD1=FIELD2  START WITH FIELD=VALUE1
ORDER BY **FIELDS**

我有本教程，但我不明白

http://blog.sqlauthority.com/2012/04/24/sql-server-introduction-to-hierarchical-query-using-a-recursive-cte-a-primer/

Answer 1

Oracle＆＃34;通过＆＃34;连接在使用其他DBMS（符合SQL标准）时，需要将语法转换为递归公用表表达式。

SQLite支持自3.8.3版https://sqlite.org/lang_with.html

以来的递归CTE

您的陈述将转换为以下内容：

with recursive my_tree as (
   select column_1, column_2, column_3
   from your_table 
   where field = value1  --- <<< this is the "start with part" in Oracle

   union all

   select c.column_1, c.column_2, c.column_3
   from your_table c
     join my_tree p           
       on p.field2 = c.field1 -- <<< this is the "prior ..." part in Oracle
) 
select *
from my_tree
order by some_column;

Oracle事先查询到SQLite

1 个答案: