select WORKINFO.*
from WORKINFO
WHERE to_char(createdate, 'yyyy') = '2015'
AND WORKINFO.IsValid = 1
AND (completeDate is not null and to_char(completeDate, 'YYYY') = '2015')
and (APPROVALDEPT in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1) or
dutydeptoid in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1))
and workStatus >= 1
and isvalid = 1
AND (extend4 = 2 or extend4 is null )
ORDER BY DutyDeptOID ASC, WorkInfoNum DESC
select WORKINFO.*
from WORKINFO
WHERE to_char(createdate, 'yyyy') = '2015'
AND WORKINFO.IsValid = 1
AND (completeDate is not null and to_char(completeDate, 'YYYY') = '2015')
and (APPROVALDEPT in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1) or
dutydeptoid in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1))
and workStatus >= 1
and isvalid = 1
AND extend4 = 2 or extend4 is null
ORDER BY DutyDeptOID ASC, WorkInfoNum DESC
from WORKINFO
WHERE to_char(createdate, 'yyyy') = '2015'
AND WORKINFO.IsValid = 1
AND (completeDate is not null and to_char(completeDate, 'YYYY') = '2015')
and (APPROVALDEPT in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1) or
dutydeptoid in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1))
and workStatus >= 1
and isvalid = 1
AND (extend4 = 2 or extend4 is null )
ORDER BY DutyDeptOID ASC, WorkInfoNum DESC
select WORKINFO.*
from WORKINFO
WHERE to_char(createdate, 'yyyy') = '2015'
AND WORKINFO.IsValid = 1
AND (completeDate is not null and to_char(completeDate, 'YYYY') = '2015')
and (APPROVALDEPT in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1) or
dutydeptoid in (select s.oid
from sysorgan s
where s.parentorganoid = 1
or s.oid = 1))
and workStatus >= 1
and isvalid = 1
AND extend4 = 2 or extend4 is null
ORDER BY DutyDeptOID ASC, WorkInfoNum DESC
or 在括号外面面,结果集是过滤其他过滤条件加extend4 = 2过滤得到的结果,再把extend4 是空过滤 得到的结果并在一起。比如:
学校有3个班级,第一个过滤条件是班级1,第二个过滤条件是 男生 或 生日在1月份的
按你的写法区别就是:
1、得到班级1里面的所有男生和1月生日的女生;
2、得到所有3个班级的1月生日的学生和班级1的男生。
2的结果比1多了班级2和班级3的1月生日的学生。明白了?