112 lines
9.1 KiB
Plaintext
112 lines
9.1 KiB
Plaintext
#---
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#schema
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#---
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#drop database if exists cte_db;
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#create database cte_db;
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#use cte_db;
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#create table emp(id int, name varchar(20), leaderid int);
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#create table t1(c1 int, c2 int, c3 int);
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#create table t2(c1 int, c2 int);
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#create table t3(c3 int primary key, c4 int);
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#
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#
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##---
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##basic cte
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##---
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#with cte(a) as (select count(c1) from t2 group by c2 limit 5) select * from cte;
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#WITH cte1 AS (SELECT c1, c2 FROM t1) select c1 from cte1;
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#WITH cte1 AS (SELECT c1, c2 FROM t1) select c1 from cte1;
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#WITH cte1 (name1, name2) AS (select c1, c2 from t1) select name1 from cte1;
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#WITH cte1 AS (SELECT c1, c2 FROM t1), cte2 AS (SELECT c1, c2 FROM t2) select c1 from cte2;
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#WITH cte1 AS (select * from t1) select c1, c2 from cte1;
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#WITH cte1 (c1)AS(select c1 from t1), cte2 AS (select * from t1) select c1, c2 from cte2;
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#WITH cte0 AS ( select * from t1) select * from cte0 for update;
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#with cte as (select count(*) from t1) select * from cte;
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#with cte as (select count(*) as k from t1) select * from cte where k = 1;
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#with cte (k1) as (select count(*) as k from t1) select * from cte where k1 = 1;
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#with cte1 (c22, c21) AS (select c1, c2 from t1) select c22 as c21, c21 from cte1 where c21 = 12;
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#with cte1 AS( select * from t1)select * from cte1 left join t2 on cte1.c1=t2.c1 having not (t2.c1 <=> cte1.c1) order by cte1.c1;
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#WITH cte1 (a, b) AS (SELECT c1, c2 FROM t1), cte2 (c, d) AS (SELECT c1, c2 FROM t2) select * from (with cte2 as(select * from t3) select c3 as c11, c4 from cte2) cte1 join cte2 on cte1.c11=cte2.c;
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#WITH cte1 (a, b) AS (SELECT c1, c2 FROM t1), cte2 (c, d) AS (SELECT c1, c2 FROM t2) select * from cte1 left join cte2 on cte1.a=cte2.c having not (cte1.b <=> cte2.d) order by cte1.a;
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#
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##---
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##recursive cte
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##---
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#WITH cte(hello) AS (SELECT c1 FROM t1 UNION ALL select hello from cte) search depth first by hello set abc select hello, abc from cte;
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#WITH cte(n) AS (SELECT c1 FROM t1 UNION ALL select n+1 from cte where n < 10) search depth first by n set a select n from cte;
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#with cte(n) as (select 1 from dual union all select n+1 from cte where n < 2) select n from cte;
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#with cte(n) as (select 1 from dual union all select n+1 from cte where n < 2) search depth first by n set abc select n,abc from cte;
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#explain with cte (a,b,c) as ( select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte where emp.leaderid = cte.a ) search depth first by a set sad select * from cte;
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#WITH cte(n) AS (SELECT c1 FROM t1 UNION ALL select n from cte) search depth first by n set a_name cycle n set iscyc to 'n' default 'y' select n from cte;
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#WITH cte(n) AS (SELECT c1 FROM t1 UNION ALL select n from cte) search depth first by n set a_name select n from cte;
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#WITH cte(n) AS (SELECT c1 FROM t1 UNION ALL select n from cte) select n from cte;
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#WITH fibonacci (n, fib_n, next_fib_n) AS ( SELECT 1, 0, 1 from dual UNION ALL SELECT n + 1, next_fib_n, fib_n + next_fib_n FROM fibonacci WHERE n < 10 ) SELECT * FROM fibonacci;
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#WITH cte(hello) AS (SELECT c1 FROM t1 UNION ALL select hello from cte) search depth first by hello set abc select hello, abc from cte;
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#WITH cte(hello) AS (SELECT c1 FROM t1 UNION ALL select hello from cte) search depth first by hello set abc select * from cte;
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#WITH cte(hello) AS (SELECT c1 FROM t1 UNION ALL select hello+1 from cte where hello < 5) search depth first by hello set abc select hello, abc from cte;
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#with cte (a,b,c) as (select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte where emp.leaderid = cte.a) search breadth first by a set sad select * from cte;
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#with cte (a,b,c) as (select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte where emp.leaderid = cte.a) cycle a set iscyc to 'n' default 'y' select * from cte;
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#explain with cte (a,b,c) as ( select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte where emp.leaderid = cte.a ) cycle a set iscyc to 'n' default 'y' select * from cte;
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#with cte (a,b,c) as ( select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte where emp.leaderid = cte.a ) cycle c set iscyc to 'n' default 'y' select * from cte;
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##with cte (a,b,c) as ( select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte where emp.leaderid = cte.a ) search breadth first by a set abc cycle a set iscyc to 'y' default 'n' select max(a) from cte start with a =1 connect by prior a = c group by level;
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#with cte(n) as (select 1 from dual) search depth first by n set abc select * from cte;
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#WITH cte1 AS (SELECT c1, c2 FROM t1) select c1 from cte1;
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#with cte(a) as (select 1 from dual union all select 2 from dual), cte_1(b) as (select 1 from dual union all select * from cte) select * from cte_1;
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#WITH cte1 (a, b) AS (SELECT c1, c2 FROM t1), cte2 (c, d) AS (SELECT c1, c2 FROM t2) select * from (with cte2 as(select * from t3) select c3 as c11, c4 from cte2) cte1 join cte2 on cte1.c11=cte2.c;
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#--error 5217
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#with cte(n) as ( select 1 from dual union all select n+1 from cte where n < 10 ) search depth first by a set abc select * from cte;
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##这两种写法oracle也是支持的，因此我们也会支持，但是这个地方其实oracle做的不合理
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##举个例子
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##with cte(n) as (select 1 from dual) cycle n set iscyc to 'y' default 'n' select n from cte;
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##oracle中，上面这条语句会报错，报主查询中的n是找不到，我们这边在非递归的cte中直接忽略了cycle和search的解析
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##符合实现oracle超集的目标
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##但是后来发现事情没有这么简单
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##假设t1表有c1，c2，c3三个列，那么下面这句
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##with cte(n,x) as (select * from t1) cycle n set iscyc to 'y' default 'n' select * from cte;
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##在oracle中会出现3个列，即c1，c2，c3, 即cte完全变成了t1表
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##这个就比较恶心了，这样的定义cte感觉有明显的错误(因为cte表的伪列数量都已经和内部子查询产出的列数量不等了)
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##应该被报错才对, 暂时不支持，OB遇到这样的语句会报错
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#with cte(n) as (select 1 from dual) search depth first by n set abc select * from cte;
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#with cte(a,b,c) as (select * from emp) search depth first by a set abc select * from cte;
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#--error 4002
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#with cte(n, x) as (select * from t1) cycle n set iscyc to 'y' default 'n' select * from cte;
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#
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#### common ###
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#with cte(n) as (select 1 union all select n+1 from cte where n < 23) select n from cte;
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#--error 4007
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#with cte(n) AS ( select 1 from cte) select * from cte;
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#--error 4007
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#with cte(n) AS (select 1 from dual UNION ALL select n+1 from (select * from cte) ct1 where n < 3) select * from cte;
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#--error 4007
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#with cte(n) AS ( select 1 from dual UNION ALL select sum(n+1) from cte) select * from cte;
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#--error 4007
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#with cte(n) as (select 1 from dual union all select c1 from t1 union all (with cte(n) as (select c1 from t1) select * from cte)) select * from cte;
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#--error 4007
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#with cte(n) AS (select 1 from dual UNION ALL select n+1 from cte where n < 3 union all select n+1 from cte where n < 2) select * from cte;
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#--error 4007
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#with cte(n) as (select n from (select 1 from dual union all select n+1 from cte) tmp) select * from cte;
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#--error 4007
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#with cte(n) AS (select 1 from cte UNION all select n+1 from cte where n < 3) select * from cte;
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#--error 4007
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#with cte(n) as (select n+1 from cte where n < 5 union all select c1 from t1) select * from cte;
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#--error 4007
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#with cte(n) as (select 1 from dual union all select * from (select n from cte where n < 5) tmp) select * from cte;
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#--error 4007
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#with cte(n) AS (select 1 from dual UNION ALL select n+1 from cte where n < 3 order by n ) select * from cte;
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#with cte_recursive (a,b,c) as ( select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte_recursive where emp.leaderid = cte_recursive.A ) search depth first by a set sad cycle b set iscyc to 'y' default 'n', cte as (select * from cte_recursive) select * from cte;
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#--error 5019
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#select * from (with cte as (select * from t2) select * from cte) t3, cte where t3.c21 = cte.c1;
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#--error 5019
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#with cte(a,b,c) as ( select c1,c2,c3 from not_exist where not_exist.c1 < 20 union all select c1,c2,c3 from not_exist, cte where cte.a = not_exist.c1 and cte.c < 10 ) select * from cte;
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#--error 4007
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#with cte(n) AS (select c1 from t1 UNION ALL select n+1 from cte right join t2 on cte.n < 3 and t2.c1 < 22) select * from cte;
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#--error 4007
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#with cte(n) AS (select c1 from t1 UNION ALL select n+1 from t2 left join cte on cte.n < 3 and t2.c1 < 22) select * from cte;
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#--error 4007
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#with cte(n) AS (select c1 from t1 UNION ALL select n+1 from t2 full join cte on cte.n < 3 and t2.c1 < 22) select * from cte;
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#--error 4007
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#with cte(n) AS (select c1 from t1 UNION ALL select n+1 from cte full join t2 on cte.n < 3 and t2.c1 < 22) select * from cte;
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#--error 4002
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#with cte (a,b,c) as (select id, name, leaderid from emp where emp.id = 1 union all select emp.id ,emp.name, emp.leaderid from emp, cte where emp.leaderid = cte.a) search depth first by a set abc cycle a set abc to 'y' default 'n' select * from cte;
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