Oracle vs PostgreSQL Develop（25） - plsql vs plpgsql（语法严谨性）

Oracle的SQL和PL/SQL语法相对宽松，而PostgreSQL则相对严格一些。

在PL/SQL中，某些语句后可以不加分号，而PG则要求必须加分号。

Oracle

创建存储过程，loop不管加不加分号，均可创建成功。

TEST-orcl@DESKTOP-V430TU3>CREATE OR REPLACE PROCEDURE proc_test(a NUMBER) as
  2  v_id number;
  3  begin
  4    for i in (select 1 from dual) loop
  5      select 2 into v_id from dual;
  6    end loop
  7    return;
  8  end;
  9  /
Procedure created.
TEST-orcl@DESKTOP-V430TU3>
TEST-orcl@DESKTOP-V430TU3>CREATE OR REPLACE PROCEDURE proc_test(a NUMBER) as
  2  v_id number;
  3  begin
  4    for i in (select 1 from dual) loop
  5      select 2 into v_id from dual;
  6    end loop;
  7    return;
  8  end;
  9  /
Procedure created.
TEST-orcl@DESKTOP-V430TU3>

PostgreSQL

创建存储过程，loop后必须加分号，才可创建成功。

[local:/data/run/pg12]:5120 pg12@testdb=# CREATE OR REPLACE PROCEDURE proc_test(pi_in int) 
pg12@testdb-# as
pg12@testdb-# $$
pg12@testdb$# declare
pg12@testdb$#   v_id int;
pg12@testdb$#   i record;
pg12@testdb$# begin 
pg12@testdb$#   for i in (select 1 from dual) loop 
pg12@testdb$#     select 2 into v_id from dual; 
pg12@testdb$#   end loop
pg12@testdb$#   return; 
pg12@testdb$# end;
pg12@testdb$# $$ LANGUAGE 'plpgsql';
t(pi_in int) 
as
$$
declare
  v_id int;
  i record;
begin 
  for i in (select 1 from dual) loop 
    select 2 into v_id from dual; 
  end loop;
  return; 
end;
$$ LANGUAGE 'plpgsql';
ERROR:  end label "return" specified for unlabelled block
LINE 11:   return; 
           ^
[local:/data/run/pg12]:5120 pg12@testdb=# 
[local:/data/run/pg12]:5120 pg12@testdb=# 
[local:/data/run/pg12]:5120 pg12@testdb=# CREATE OR REPLACE PROCEDURE proc_test(pi_in int) 
pg12@testdb-# as
pg12@testdb-# $$
pg12@testdb$# declare
pg12@testdb$#   v_id int;
pg12@testdb$#   i record;
pg12@testdb$# begin 
pg12@testdb$#   for i in (select 1 from dual) loop 
pg12@testdb$#     select 2 into v_id from dual; 
pg12@testdb$#   end loop;
pg12@testdb$#   return; 
pg12@testdb$# end;
pg12@testdb$# $$ LANGUAGE 'plpgsql';
CREATE PROCEDURE
[local:/data/run/pg12]:5120 pg12@testdb=# 
[local:/data/run/pg12]:5120 pg12@testdb=#

参考资料

N/A