Considerations for compatibility with Oracle and DB2 Development

We are working on compatibilityOralce,Db2During development, you need to pay attention to some issues to avoid incompatibility and problems for developers. In this example, the premise is that the db2 version is 9.7 and the database is created after the PLSQL compilation option is enabled. Next we will begin to introduce these.

Note:

1. If table fields are used after like, they should be replaced with the locate function. For example:

Oralce statement:

 
 

  
  
select * from fw_right a where '03' like a.rightid||'%'; 
 
 

Compatible Syntax:

 
 

  
  
select * from fw_right a where locate('03',a.rightid) = 1; 
 
 

Oralce statement:

 
 

  
  
select * from fw_right a where '03' like '%'||a.rightid||'%'; 
 
 

Compatible Syntax:

 
 

  
  
select * from fw_right a where locate('03',a.rightid) > 0; 
 
 

2. aliases used in views should not have the same name as the current table field.

If the following statement is used, the error "SQL0153N" is reported in db2.

 
 

  
  
CREATE OR REPLACE VIEW V_WF_TODOLIST AS  
  
  
 
  
  
select c.process_def_id, c.process_def_name, a.action_def_id,  
  
  
 
  
  
a.work_item_id, a.bae007, a.action_def_name,  
  
  
 
  
  
a.state,  a.pre_wi_id,  a.work_type,  
  
  
 
  
  
a.operid, a.x_oprator_ids,  b.process_key_info,  
  
  
 
  
  
to_char(to_date(a.start_time, 'yyyymmddhh24miss'),'yyyy-mm-dd hh24:mi:ss') as start_time,  
  
  
 
  
  
to_char(to_date(a.complete_time,'yyyymmddhh24miss'),'yyyy-mm-dd hh24:mi:ss') as complete_time,  
  
  
 
  
  
a.filter_opr, a.memo,a.bae002,a.bae003, a.bae006,c.x_action_def_ids  
  
  
 
  
  
from wf_work_item a, wf_process_instance b, wf_action_def c  
  
  
 
  
  
where a.action_def_id  = c.action_def_id  
  
  
 
  
  
and b.process_def_id = c.process_def_id  
  
  
 
  
  
and a.bae007 = b.bae007  
  
  
 
  
  
and a.state in('0','2') 
 
 

Compatible Syntax:

 
 

  
  
CREATE OR REPLACE VIEW V_WF_TODOLIST AS  
  
  
 
  
  
select c.process_def_id, c.process_def_name, a.action_def_id,  
  
  
 
  
  
a.work_item_id, a.bae007, a.action_def_name,  
  
  
 
  
  
a.state,  a.pre_wi_id,  a.work_type,  
  
  
 
  
  
a.operid, a.x_oprator_ids,  b.process_key_info,  
  
  
 
  
  
to_char(to_date(a.start_time, 'yyyymmddhh24miss'),'yyyy-mm-dd hh24:mi:ss') as start_time_0,  
  
  
 
  
  
to_char(to_date(a.complete_time,'yyyymmddhh24miss'),'yyyy-mm-dd hh24:mi:ss') as complete_time_0,  
  
  
 
  
  
a.filter_opr, a.memo,a.bae002,a.bae003, a.bae006,c.x_action_def_ids  
  
  
 
  
  
from wf_work_item a, wf_process_instance b, wf_action_def c  
  
  
 
  
  
where a.action_def_id  = c.action_def_id  
  
  
 
  
  
and b.process_def_id = c.process_def_id  
  
  
 
  
  
and a.bae007 = b.bae007  
  
  
 
  
  
and a.state in('0','2') 
 
 

3. order by or fetch first n rows only is not allowed in the following cases:

• Full outer query view
• Full outer query in the RETURN Statement of "SQL table function"
• Specific query table definition
• Subqueries without parentheses

Otherwise, "SQL20211N specification order by or fetch first n rows only is invalid. "Error.

Oralce statement:

 
 

  
  
CREATE OR REPLACE VIEW V_FW_BLANK_BULLETIN as  
  
  
 
  
  
select id, bae001,  operunitid, operunittype, unitsubtype, ifergency,  
  
  
 
  
  
title,  content, digest,  duetime,  validto, aae100,  
  
  
 
  
  
bae006, bae002,  bae003,  id as colid,  
  
  
 
  
  
substr(digest,1,20) as digest2  
  
  
 
  
  
from fw_bulletin  
  
  
 
  
  
where duetime <= to_char(sysdate,'yyyymmddhh24miss')  
  
  
 
  
  
and (to_char(validto) >= to_char(sysdate,'yyyymmddhh24miss') or validto is null)  
  
  
 
  
  
and aae100 ='1' 
  
  
 
  
  
order by ifergency desc, id desc,  duetime desc 
 
 

Compatible Syntax:

 
 

  
  
CREATE OR REPLACE VIEW V_FW_BLANK_BULLETIN as  
  
  
 
  
  
select * from (select id, bae001,  operunitid, operunittype, unitsubtype, ifergency,  
  
  
 
  
  
title,  content, digest,  duetime,  validto, aae100,  
  
  
 
  
  
bae006, bae002,  bae003,  id as colid,  
  
  
 
  
  
substr(digest,1,20) as digest2  
  
  
 
  
  
from fw_bulletin  
  
  
 
  
  
where duetime <= to_char(sysdate,'yyyymmddhh24miss')  
  
  
 
  
  
and (to_char(validto) >= to_char(sysdate,'yyyymmddhh24miss') or validto is null)  
  
  
 
  
  
and aae100 ='1' 
  
  
 
  
  
order by ifergency desc, id desc,  duetime desc) 
 
 

After learning about the preceding precautions during Oracle and DB2 development, we can avoid incompatibility issues as much as possible during development. This article will introduce you here, hoping to help you.