在开发项目的过程中,发现如下异常:原因是updateType字段为int类型,不能接收null,而在数据库中对应的字段为null,解决方法:将updateType字段类型改为Integer。
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数据库 时间:
2015-03-18 19:54:54
阅读次数:
179
“assigned”主键由外部程序负责生成,在 save() 之前指定一个。“hilo”通过hi/lo 算法实现的主键生成机制,需要额外的数据库表或字段提供高位值来源。“seqhilo”与hilo 类似,通过hi/lo 算法实现的主键生成机制,需要数据库中的 Sequence,适用于支持 Seque...
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Web程序 时间:
2015-03-17 19:37:45
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192
在Hibernate中,提供了主键生成策略。下面是比较常用的几种:? 1:assigned? ----表示在新增数据时由应用程序指定主键的值。主要针对主键是采用自然主键的形式。这种方式,适用于主键列不是自动增长列。? 其缺...
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Web程序 时间:
2015-03-16 08:44:44
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224
题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2426For any school, it is hard to find a feasible accommodation plan with every student assigned to a s...
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编程语言 时间:
2015-03-15 13:37:30
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166
A table tennis club has N tables available to the public. The tables are numbered from 1 to N. For any pair of players, if there are some tables open when they arrive, they will be assigned to the ava...
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其他好文 时间:
2015-03-02 19:10:02
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126
Hibernate自定义主键,通过此方法可以解决一此特殊的主键ID,在了解自定义主键时,先了解下Hibernate有自带的10种生成主键方法.1) assigned主键由外部程序负责生成,无需Hibernate参与。推荐此种方法,在实体配置中修改如下: ...
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Web程序 时间:
2015-02-28 18:30:18
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151
1 题目There areNchildren standing in a line. Each child is assigned a rating value.You are giving candies to these children subjected to the following r...
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其他好文 时间:
2015-02-28 00:06:36
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211
Given a non-empty tree with root R, and with weight Wi assigned to each tree node Ti. The weight of a path from R to L is defined to be the sum of the...
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其他好文 时间:
2015-02-26 13:02:16
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226
There areNchildren standing in a line. Each child is assigned a rating value.You are giving candies to these children subjected to the following requi...
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其他好文 时间:
2015-02-25 23:39:26
阅读次数:
202
In my stochastic processes class, Prof Mike Steele assigned a homework problem to calculate the ruin probabilities for playing a game where you with $...
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其他好文 时间:
2015-02-23 09:36:56
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382