Should I use composite primary keys if I use JPA and the keys can change?
我应该使用复合主键如果我使用JPA和键可以改变吗?
Multiple attributes in the entity may be combined to form a composite primary key.
实体中的多个属性可以组合成一个复合的主键。
You can adjust the primary-key creation strategy or even specify a composite primary key.
可以调整主键的生成策略,甚至指定复合主键。
Creating a composite application that increases productivity is your primary goal, but we all know that applications are not static and must always adapt to the changing needs of business.
您的主要目标是创建提高生产力的复合应用程序,但是我们都知道,应用程序不是静态的,并且必须总是随业务需求的变更而变化。
You can also create a primary key class for entities that have composite keys.
还可以为具有组合键的实体创建一个主键类。
You can see that the primary key is indeed a composite made up of the street and city fields.
可以看到,主键实际上是由street和city字段组合而成的。
Quadrilateral partition on triangular meshes data is the primary process of composite surface modeling.
四边形网格划分是组合曲面建模技术的首要条件。
The primary end point was a composite of death, myocardial reinfarction, or New York Heart Association (NYHA) class IV heart failure.
主要结果为对死亡,心肌梗死再复发或者纽约心脏协会(NYHA)分级的IV级心脏衰竭的综合评价。
The primary end point was a composite of EF, distance on a 6-min walk test and Minnesota Living with Heart Failure Questionnaire (MLWHF) score.
主要终点事件是射血分数、6分钟步行实验、明尼苏达生活质量分数的复合。
Main Outcome Measures The primary end point was a composite of initial fatal or nonfatal coronary event or stroke or revascularization.
复合终点为初次致命或非致命性冠状动脉事件、卒中和血管重建。
Dishwashing detergent is the composite system of primary surfactants, secondary surfactants and auxiliary compositions according to a certain formulation.
餐具洗涤剂由主要表面活性剂,次要表面活性剂及辅助成分按一定配方复配而成。
Making explanation of the design principle of composite pile, and providing the primary data in accordance with the field test of composite pile under the loading of high subgrade in this project.
解释了设计复合桩的原理,针对该工程的高路基荷载下复合桩进行了现场测试,提供了初步的数据。
Mixing method is the primary approach for getting highperformance cement-based composite materials and fibrous reinforcement is core.
复合化是水泥基材料高性能化的主要途径,纤维增强是核心。
The fibre volume fraction is the primary physical performance parameter, while the mechanical research focuses on the composite elastic properties.
纤维体积分数是物理性能研究的最主要参数,力学分析以复合材料的弹性性能为主。
Abstract :Failure process of a primary load-bearing composite joint in wing root was analyzed by finite element methods, and the ultimate strength of the joint was predicted.
以复合材料机翼翼根后梁下缘条对接试件为研究对象,通过有限元手段分析其失效机理和破坏过程,并对极限强度进行预测。
The primary end point was a composite of myocardial infarction or death from cardiac causes.
主要复合终点是心肌梗死或心脏原因所致死亡。
The key secondary composite outcome was the primary outcome plus hospitalization for unstable angina.
次要复合终点为不稳定性心绞痛附加住院的主要转归。
Sun in the second house of the composite chart is the best possible position for any business or professional relationship whose primary aim is to make money or to gather material possessions.
太阳位于合成图中的第二宫,这对任何赚钱或积累物质财富的商业或职业关系来说,都是最佳的位置。
The calculation of structural load on the lining of tunnel with shallow overburden shows that the load on composite lining will be shared by primary support and secondary lining.
隧道衬砌在浅埋段的结构荷载计算表明,复合式衬砌中的初期支护和二次衬砌一般要共同承担荷载。
Data Extraction The primary outcome was a composite of cardiovascular death, MI, or stroke. The secondary outcome was all-cause mortality.
资料提取主要结果指标是心血管病死亡,心肌梗死或卒中总和数据,次要结果指标是总死亡率。
The primary outcome was a composite of cardiovascular death, MI, or stroke. The secondary outcome was all-cause mortality.
主要结局为心血管死亡、心梗和卒中的总和,次要结局为全因死亡率。
Combined with practical work, the application of composite profile method and apparent resistivity sounding method in primary de-sign of building project is introduced.
结合工程实例,介绍了联合剖面法、视电阻率测深法在土建项目初步设计中的应用,解释了其应用中的异常特征与推断,为项目初步设计提供工程水文地质依据。
Primary end points were the rate of death and a composite of death, myocardial infarction, or stroke (major cardiovascular events).
主要研究点是死亡率和多因素死亡、心肌梗死或中风(主要心血管事件)发生率。
Primary end points were the rate of death and a composite of death, myocardial infarction, or stroke (major cardiovascular events).
主要研究点是死亡率和多因素死亡、心肌梗死或中风(主要心血管事件)发生率。
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