aterydb(PostgreSQL)                                         Sybase

1.两个字符串连接 

select 'abc'||'def';                                          select  'a'+'b';

2. 字段类型转换

select  cast（1 as varchar(4)）；                     select convert(varchar,1);

3. 求字段值得assci 码

select assci('abc') ;                                                                select assci('abc') ;  

4.获得当前时间

select now();                                        select getdate();   

select  intNum1 +(_) intNum2                    select  intNum1 +(-) intNum2

5.主键生成策略

        尚未发现                                                        c_id  int  identify  not  null         

6.判断某表的某字段是否为null,如果是null ,则。。。

select  coalesce(names, '无名氏') as wk_ptn_cd  from test.tab;

select  isnull(names, '无名氏') as wk_ptn_cd  from tab;

7. 删除已经存在的视图

drop view if exists viewName

if exists( select 1 from sysobjects  where type='V' and name= 'V_ORGAN_GXGX')

  drop view V_ORGAN_GXGX