高人指点Firebird存储过程

[jrwjrw]

我要把这句SQL改写成存储过程：
string sql = string.Format("select sum((SELLSUM+SERVICESUM)-SELLCOSTSUM) from tb_coaccount where COSTOBJECT='{0}' and SECTOR='{1}'and ORDERDATE like '%{2}%'", CostOjbect, ProfitSector, ProfitDate);

存储过程是这样的，但报错：
BEGIN
select sum((SELLSUM+SERVICESUM)-SELLCOSTSUM) from tb_coaccount
where COSTOBJECT=:t_costobject and SECTOR=:t_sector and ORDERDATE like :t_orderdate;
END
请教编辑器里德写法

全的DDL
SET TERM ^ ;

CREATE PROCEDURE PR_COACCOUNT_SUM (
ORDERDATE DATE,
SECTOR VARCHAR(20),
COSTOBJECT VARCHAR(20))
AS
DECLARE VARIABLE T_SECTOR VARCHAR(20);
DECLARE VARIABLE T_COSTOBJECT VARCHAR(20);
DECLARE VARIABLE T_ORDERDATE DATE;
BEGIN
select sum((SELLSUM+SERVICESUM)-SELLCOSTSUM) from tb_coaccount
where COSTOBJECT=:t_costobject and SECTOR=:t_sector and ORDERDATE like :t_orderdate;
END
^

SET TERM ; ^