Data storage solutions are a crucial aspect of any application, significantly impacting data management and system performance. This article explores the rationale behind utilizing both SQL and NoSQL databases, addres...Data storage solutions are a crucial aspect of any application, significantly impacting data management and system performance. This article explores the rationale behind utilizing both SQL and NoSQL databases, addressing key questions about when each type is preferable. The background emphasizes the importance of selecting the appropriate database technology to meet specific application requirements. The purpose of this research is to provide a comprehensive guide for choosing between SQL and NoSQL databases based on various factors, including workload characteristics, scalability needs, and consistency requirements. To achieve this, we examine different strategies for implementing SQL and NoSQL databases in large-scale distributed applications and systems. The research method involves a comparative analysis of the features, advantages, and limitations of both database types. We specifically focus on scenarios involving read-heavy versus write-heavy systems and the trade-offs between availability and consistency. The results of this research indicate that SQL databases, with their relational structure and ACID compliance, are ideal for applications requiring complex queries and data integrity. In contrast, NoSQL databases, offering schema flexibility and horizontal scalability, are better suited for managing extensive datasets and high-velocity data ingestion. In conclusion, the selection of a database depends on the specific needs of the application. SQL databases are preferred for transactional systems with complex relationships, while NoSQL databases excel in scenarios demanding flexibility and scalability. The study provides insights into hybrid approaches, leveraging both database types to optimize system performance.展开更多
Nuonuo Kids Bookstore is a dreamlike reading kingdom,established by Zhaci and his team with boundless enthusiasm and considerate design.In such a magical space,laughters and exclamations of kids harmonize into the mos...Nuonuo Kids Bookstore is a dreamlike reading kingdom,established by Zhaci and his team with boundless enthusiasm and considerate design.In such a magical space,laughters and exclamations of kids harmonize into the most beautiful melody.Here,they learn to think,feel,love and also be loved.展开更多
消费者体验需求的提升促使零售商不断探索新渠道模式,以提高原有实体店效益的同时优化线上经营策略。本文分别考虑传统BORO(buy online and return online)和开通BOPS(buy online and pickup in store)两种渠道情形,构建零售商针对消费...消费者体验需求的提升促使零售商不断探索新渠道模式,以提高原有实体店效益的同时优化线上经营策略。本文分别考虑传统BORO(buy online and return online)和开通BOPS(buy online and pickup in store)两种渠道情形,构建零售商针对消费者线上购买并在线上或线下退款的差异化退货策略利润模型,分析两种渠道情形下的最优定价和最优退货策略,进而考虑BOPS渠道的溢出效应,分析零售商在相同退货策略下是否应该开通BOPS渠道。结果表明:(1)在两种情形下,随着线下商店数量的增多,零售商均会倾向于在低开店成本下选择全额退款策略,倾向于在高开店成本下选择部分退款策略;(2)在同渠道情形下,全额退款策略的定价始终低于部分退款策略。在同退货策略下,BOPS情形下的定价始终低于BORO情形;(3)高溢出效应和多商店数量都促使零售商选择开通BOPS渠道,但商店数量决定了BOPS线下麻烦成本规模因子对零售商开通BOPS渠道起推动还是抑制作用。本文为既定商店数量下多渠道零售商退货策略与渠道选择提供了决策支持。展开更多
目的观察冷藏保存血小板(cold stored platelets,CSP)在外科出血患者的治疗效果及不良反应。方法一项前瞻性、双盲、随机临床试验对伴有外科出血患者进行研究,以评估CSP与室温保存血小板(room temperature platelets,RTP)的止血功能。...目的观察冷藏保存血小板(cold stored platelets,CSP)在外科出血患者的治疗效果及不良反应。方法一项前瞻性、双盲、随机临床试验对伴有外科出血患者进行研究,以评估CSP与室温保存血小板(room temperature platelets,RTP)的止血功能。主要结局是评价引流量、血小板计数和血栓弹力图-最大振幅(thromboelastography,maximum amplitude,TEG-MA)。次要结局包括住院时间、重症监护室(ICU)住院时间、医疗花费。结果共有62例患者完成了最后的临床观察,CSP组和RTP组各31例。血小板输注以后1~12 h,13~24 h,25~48 h,49~72 h的引流量分别为:8.5 mL/h vs 20.83 mL/h,0.52 mL/h vs 5.0 mL/h,3.5 mL/h vs 5.0 mL/h,0.63 mL/h vs 4.1 mL/h。血小板计数:58×10^(9)/L vs 79×10^(9)/L,54×10^(9)/L vs 77×10^(9)/L,63×10^(9)/L vs 75×10^(9)/L,66×10^(9)/L vs 79×10^(9)/L。TEG-MA:50.1 mm vs 52.0 mm,50.1 mm vs 54.8 mm,53.0 mm vs 56.6,56.0 mm vs 53.2 mm。根据广义估计方程,两组在不同时间的P_(drainage)=0.933,P_(PLT计数)=0.473,P_(TEG-MA)=0.246,差异无统计学意义(P>0.05)。住院时间、ICU住院时间、医疗费用、出院结局在CSP组与RTP组比较差异无统计学意义(P>0.05)。两组患者血小板输注不良事件发生率差异无统计学意义(P>0.05)。结论CSP与RTP在外科大出血治疗中具有相同的治疗效果和安全性,本研究为临床应用CSP提供了可信的证据支持。展开更多
文摘Data storage solutions are a crucial aspect of any application, significantly impacting data management and system performance. This article explores the rationale behind utilizing both SQL and NoSQL databases, addressing key questions about when each type is preferable. The background emphasizes the importance of selecting the appropriate database technology to meet specific application requirements. The purpose of this research is to provide a comprehensive guide for choosing between SQL and NoSQL databases based on various factors, including workload characteristics, scalability needs, and consistency requirements. To achieve this, we examine different strategies for implementing SQL and NoSQL databases in large-scale distributed applications and systems. The research method involves a comparative analysis of the features, advantages, and limitations of both database types. We specifically focus on scenarios involving read-heavy versus write-heavy systems and the trade-offs between availability and consistency. The results of this research indicate that SQL databases, with their relational structure and ACID compliance, are ideal for applications requiring complex queries and data integrity. In contrast, NoSQL databases, offering schema flexibility and horizontal scalability, are better suited for managing extensive datasets and high-velocity data ingestion. In conclusion, the selection of a database depends on the specific needs of the application. SQL databases are preferred for transactional systems with complex relationships, while NoSQL databases excel in scenarios demanding flexibility and scalability. The study provides insights into hybrid approaches, leveraging both database types to optimize system performance.
文摘Nuonuo Kids Bookstore is a dreamlike reading kingdom,established by Zhaci and his team with boundless enthusiasm and considerate design.In such a magical space,laughters and exclamations of kids harmonize into the most beautiful melody.Here,they learn to think,feel,love and also be loved.
文摘消费者体验需求的提升促使零售商不断探索新渠道模式,以提高原有实体店效益的同时优化线上经营策略。本文分别考虑传统BORO(buy online and return online)和开通BOPS(buy online and pickup in store)两种渠道情形,构建零售商针对消费者线上购买并在线上或线下退款的差异化退货策略利润模型,分析两种渠道情形下的最优定价和最优退货策略,进而考虑BOPS渠道的溢出效应,分析零售商在相同退货策略下是否应该开通BOPS渠道。结果表明:(1)在两种情形下,随着线下商店数量的增多,零售商均会倾向于在低开店成本下选择全额退款策略,倾向于在高开店成本下选择部分退款策略;(2)在同渠道情形下,全额退款策略的定价始终低于部分退款策略。在同退货策略下,BOPS情形下的定价始终低于BORO情形;(3)高溢出效应和多商店数量都促使零售商选择开通BOPS渠道,但商店数量决定了BOPS线下麻烦成本规模因子对零售商开通BOPS渠道起推动还是抑制作用。本文为既定商店数量下多渠道零售商退货策略与渠道选择提供了决策支持。
文摘目的观察冷藏保存血小板(cold stored platelets,CSP)在外科出血患者的治疗效果及不良反应。方法一项前瞻性、双盲、随机临床试验对伴有外科出血患者进行研究,以评估CSP与室温保存血小板(room temperature platelets,RTP)的止血功能。主要结局是评价引流量、血小板计数和血栓弹力图-最大振幅(thromboelastography,maximum amplitude,TEG-MA)。次要结局包括住院时间、重症监护室(ICU)住院时间、医疗花费。结果共有62例患者完成了最后的临床观察,CSP组和RTP组各31例。血小板输注以后1~12 h,13~24 h,25~48 h,49~72 h的引流量分别为:8.5 mL/h vs 20.83 mL/h,0.52 mL/h vs 5.0 mL/h,3.5 mL/h vs 5.0 mL/h,0.63 mL/h vs 4.1 mL/h。血小板计数:58×10^(9)/L vs 79×10^(9)/L,54×10^(9)/L vs 77×10^(9)/L,63×10^(9)/L vs 75×10^(9)/L,66×10^(9)/L vs 79×10^(9)/L。TEG-MA:50.1 mm vs 52.0 mm,50.1 mm vs 54.8 mm,53.0 mm vs 56.6,56.0 mm vs 53.2 mm。根据广义估计方程,两组在不同时间的P_(drainage)=0.933,P_(PLT计数)=0.473,P_(TEG-MA)=0.246,差异无统计学意义(P>0.05)。住院时间、ICU住院时间、医疗费用、出院结局在CSP组与RTP组比较差异无统计学意义(P>0.05)。两组患者血小板输注不良事件发生率差异无统计学意义(P>0.05)。结论CSP与RTP在外科大出血治疗中具有相同的治疗效果和安全性,本研究为临床应用CSP提供了可信的证据支持。
