Postgresql 中的表值参数等效项

Question

在 postgresql 中 - 什么是具有表值参数（MSSQL）的存储过程的等价物？

Answer 1

PostgreSQL 没有表变量。最相似的类型是composite array：

create type foo_typ as (a int, b int);

do $$
declare
  f foo_typ[];
  r foo_typ;
begin
  f := ARRAY(SELECT row(10, 20)::foo_typ from generate_series(1,10));
  for r in select * from unnest(f) g(v)
  loop
    raise notice 'a:%, b:%', r.a, r.b;
  end loop;
end;
$$;
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
NOTICE:  a:10, b:20
DO

在 PostgreSQL 中编写存储过程，在语法熟悉度方面，您实际上是从 T-SQL 零开始的。PostgreSQL 语法与 Oracle 和 DB2 类似，但与 SQL Server 非常不同。

Answer 2

@HamidKhan - 你的开发语言是Java还是C#？

CREATE TABLE public.employee (
  emp_id INTEGER NOT NULL,
  emp_nm VARCHAR(40),
  first_in_time TIMESTAMP WITH TIME ZONE DEFAULT clock_timestamp(),
  last_chg_time TIMESTAMP WITH TIME ZONE DEFAULT clock_timestamp(),
  CONSTRAINT employee_pkey PRIMARY KEY(emp_id)
)
WITH (oids = false);

CREATE TYPE public.employee_udt AS (
  emp_id INTEGER,
  emp_nm VARCHAR(40)
);

--c# 代码 1

public class EmployeeUdt
{
    [PgName("emp_id")] 
    public int EmpId { get; set; } 

    [PgName("emp_nm")]
    public string EmpNm { get; set; }
}

--c# 代码 2

List<EmployeeUdt> lst_param = new List<EmployeeUdt>();

for (int i = 0; i < this.dataGridView1.Rows.Count; i++)
{
lst_param.Add(
new EmployeeUdt
{
    EmpId = Convert.ToInt32(this.dataGridView1[0, i].Value),
    EmpNm = this.dataGridView1[1, i].Value.ToString()
}
);
}

var _param = new[] {
new NpgsqlParameter
{
    ParameterName="p_employee",
    NpgsqlDbType = NpgsqlDbType.Composite,
    SpecificType = typeof(EmployeeUdt[]),
    NpgsqlValue = lst_param
}

};

SqlHelper.ExecuteNonQuery<EmployeeUdt>(this.connstring, "usp_set_emp", _param);