ibatis 常用标签

prepend:自动在前面加上;自动新手;自动预;自动前置

property:属性

compareValue:指定的常数,值

 1 //判断不相等:
 2 
 3 <isNotEqual prepend=" and " property="name" compareValue="intnumber">
 4 
 5   ===条件===
 6 
 7 </isNotEqual>
 8 
 9  
10 
11 //判断相等:
12 
13 <isEqual prepend="and"  property="name" compareValue="value">
14 
15   ===条件===
16 
17 < /isEqual>
18 
19 20 
21 <isEqual prepend="and"  property="name" compareProperty="value">
22 
23   ===条件===
24 
25 < /isEqual>
26 
27 //判断是否为空或null:
28 
29 <isEmpty prepend="and" property="name">
30 
31   ===条件===    
32 
33 </isEmpty> 
34 
35 <isNull prepend="and" property="name">
36 
37   ===条件===      
38 
39  </isNull>
40 
41 //判断不为空或不为null:
42 
43 
44 <isNotEmpty prepend="and" property="name">
45 
46 
47   ===条件===    
48 
49 
50 </isNotEmpty> 
51 
52 
53 <isNotNull prepend="and" property="name">
54 
55 
56   ===条件===      
57 
58 
59  </isNotNull>
示例

注意:

在iBATIS中

isEmpty判断参数是否为Null或者空,满足其中一个条件则其true

isNotEmpty相反,当参数既不为Null也不为空是其为true

而:isNull、isNotNull,只判断是否为null

判断之后做相对应的表达式操作

灵活运用:

 1 select * from gr_xx  where 1=1
 2 
 3 <isNotNull prepend="and" property="name">
 4 
 5   bzhm=#name#
 6 
 7  </isNotNull>
 8 
 9 
10 update gr_xx  
11 
12 <isNotNull prepend="set" property="xm">
13 
14   xm=#xm#
15 
16  </isNotNull>
17 
18 <isNotNull prepend="," property="bzhm">
19 
20   bzhm=#bzhm#
21 
22  </isNotNull>
示例

 

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原文地址:https://www.cnblogs.com/baby-zhude/p/4182836.html