Database keys
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Database keys are used to establish relationships between tables in a relational database and uniquely identify records. There are several types of keys: super keys identify tuples within a relation using one or more attributes; candidate keys are minimal super keys; the primary key is the candidate key chosen to uniquely identify tuples; alternate keys are other candidate keys not used as the primary key; a composite key is a primary key formed from multiple attributes; and a foreign key in one table references the primary key in another table to link the tables.
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Types of keys in database | SQL
The document discusses different types of keys in database management systems (DBMS). It defines keys as attributes that help uniquely identify rows in database tables. The main types of keys discussed are primary keys, foreign keys, candidate keys, alternate keys, composite keys, and super keys. Primary keys uniquely identify each row and cannot contain null values or duplicates. Foreign keys link rows between tables. Candidate keys could serve as primary keys but only one is chosen. Alternate and composite keys provide other unique identifiers. Super keys may contain non-key attributes. Keys help maintain data integrity and relationships between tables in a DBMS.
Key and its different types
This document defines and provides examples of different types of keys in a database table:
1) A super key is an attribute or combination of attributes that can identify records, but it may contain redundant data. A candidate key is a minimal super key that uniquely identifies each record.
2) The primary key is the candidate key chosen by the database designer to uniquely identify each record. It can consist of one or more attributes.
3) A foreign key is an attribute in one table that references the primary key of another table, enforcing referential integrity between the tables.
4) If the primary key contains multiple attributes, it is called a composite or compound key.
Types of keys dbms
The document discusses different types of keys used in database management systems. It defines primary key as a minimal set of attributes that uniquely identify each row in a table. It also discusses candidate keys, alternate keys, super keys, composite keys, and foreign keys. Candidate keys are attributes that qualify for uniqueness. Alternate keys are other candidate keys besides the primary key. Super keys are attributes that include the primary key attributes. Composite keys are formed using multiple attributes when no single attribute uniquely identifies rows. Foreign keys link tables and enforce referential integrity.
Database Keys
A key is a field or set of fields that uniquely identifies each record in a table. A candidate key is a field or set of fields that could serve as the primary key. The primary key is the candidate key that is chosen to uniquely identify each record. When no single field can uniquely identify records, a compound key that combines multiple fields can be used. A surrogate key is a unique identifier created specifically to identify records when the natural candidate keys do not adequately distinguish between records. Foreign keys are used to link records between tables based on matching primary key values.
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The document defines and provides examples of different types of keys used in database systems, including super keys, candidate keys, primary keys, alternate keys, composite keys, foreign keys, and unique keys. A super key can identify a tuple but contains extra attributes, while a candidate key is a minimal super key. The primary key is chosen by the administrator and must be unique. Alternate keys are other candidate keys, and composite keys comprise multiple attributes. Foreign keys link tables using primary keys, and unique keys are like primary keys but allow null values.
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Types of keys in database | SQL
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This document defines and provides examples of different types of keys in a database table:
1) A super key is an attribute or combination of attributes that can identify records, but it may contain redundant data. A candidate key is a minimal super key that uniquely identifies each record.
2) The primary key is the candidate key chosen by the database designer to uniquely identify each record. It can consist of one or more attributes.
3) A foreign key is an attribute in one table that references the primary key of another table, enforcing referential integrity between the tables.
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The document discusses different types of keys used in database management systems. It defines primary key as a minimal set of attributes that uniquely identify each row in a table. It also discusses candidate keys, alternate keys, super keys, composite keys, and foreign keys. Candidate keys are attributes that qualify for uniqueness. Alternate keys are other candidate keys besides the primary key. Super keys are attributes that include the primary key attributes. Composite keys are formed using multiple attributes when no single attribute uniquely identifies rows. Foreign keys link tables and enforce referential integrity.
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A key is a field or set of fields that uniquely identifies each record in a table. A candidate key is a field or set of fields that could serve as the primary key. The primary key is the candidate key that is chosen to uniquely identify each record. When no single field can uniquely identify records, a compound key that combines multiple fields can be used. A surrogate key is a unique identifier created specifically to identify records when the natural candidate keys do not adequately distinguish between records. Foreign keys are used to link records between tables based on matching primary key values.
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3. Referential integrity constraints maintain relationships between tables by preventing actions that would invalidate links between foreign and primary keys.
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This document defines and explains different types of keys used in relational database management systems. It describes super keys as any set of attributes that uniquely identify a record, with primary keys being a single attribute that uniquely identifies each record. Candidate keys are minimal super keys, and alternate keys are candidate keys other than the primary key. Foreign keys link two tables by referencing the primary key of one table from another table.
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The following presentation represents database keys and its types, and also database relationship and its types with references. It will help you to know about what is keys and database relationship.
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For more information visit https://tutsmaster.org/
DATA BASE KEYS.docx
A key is an attribute or set of attributes that uniquely identifies records in a table. The document defines different types of keys such as super keys, candidate keys, primary keys, alternate keys, foreign keys, and composite keys. It also explains the purpose of each key and provides examples from sample tables to illustrate the different key concepts.
B & c
RDBMS stands for Relational Database Management System. It stores data in tables with rows and columns and provides operators to manipulate the data. RDBMS uses SQL as its query language. The leading RDBMS products are Oracle, IBM DB2, and Microsoft SQL Server. Keys like primary keys and foreign keys are used to identify rows and relate tables through common columns. Data integrity rules constrain column values to ensure consistency.
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3. Referential integrity constraints maintain relationships between tables by preventing actions that would invalidate links between foreign and primary keys.
4. Cascade rules extend referential integrity by automatically propagating updates or deletes from a primary table to its related tables.
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This document defines and explains different types of keys used in relational database management systems. It describes super keys as any set of attributes that uniquely identify a record, with primary keys being a single attribute that uniquely identifies each record. Candidate keys are minimal super keys, and alternate keys are candidate keys other than the primary key. Foreign keys link two tables by referencing the primary key of one table from another table.
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2. Relational integrity constraints include key constraints, domain constraints, and referential integrity constraints to ensure valid data.
3. Relational algebra and calculus provide theoretical foundations for query languages like SQL. Relational algebra uses operators like select, project, join on relations, while relational calculus specifies queries using logic.
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Database Relationships
- Database tables can be linked together through relationships that connect common fields, called primary keys, between tables. This allows data to be stored separately but managed and retrieved collectively.
- A relationship links data between individual tables and increases the usefulness of a database. A primary key uniquely identifies each record in a table and is used to link tables together through relationships.
- Junction tables are used to join primary keys from multiple tables and allow those tables to share information through a many-to-many relationship.
Database Keys & Relationship
The following presentation represents database keys and its types, and also database relationship and its types with references. It will help you to know about what is keys and database relationship.
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Packages in PL/SQL group logically related types, variables, and subprograms. A package has a specification and body. The specification declares public objects available outside the package. The body defines private objects and code for methods in the specification. Public package elements can be called using package_name.element_name. Packages allow organizing program logic and controlling access.
Trigger
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3. A data dictionary contains metadata about the database structure and access permissions.
Presentation OF DBMS-2.pptx
The document discusses different types of keys used in database management systems (DBMS) to uniquely identify and relate data between tables. It defines keys such as primary keys, foreign keys, candidate keys, surrogate keys, composite keys and others. For example, it states that a primary key uniquely identifies each row in a table and cannot be duplicate, while a foreign key creates a relationship between two tables by referencing the primary key of another table.
key.pptx
The document defines and describes different types of keys used in database management systems. It discusses primary keys, candidate keys, alternate keys, composite keys, super keys, and foreign keys. A primary key uniquely identifies each record in a table and cannot contain null values. Candidate keys and alternate keys can also uniquely identify records. Composite keys consist of multiple attributes that uniquely identify records. Super keys can uniquely identify records but may contain extra attributes and allow null values. Foreign keys link data between tables by pointing to the primary key of another table and can contain null values.
DBMS_Keys.pdf
1) There are different types of keys in a database including primary keys, candidate keys, alternate keys, super keys, composite keys, and foreign keys.
2) Primary keys uniquely identify each record in a table and cannot contain null values or be modified.
3) Candidate keys are attributes that qualify as primary keys and are minimal super keys. Alternate keys are other candidate keys besides the primary key.
Similar to Database keys (20)
Database Systems - Relational Data Model (Chapter 2)
Database Systems - Relational Data Model (Chapter 2)
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My burning issue is homelessness K.C.M.O.
My burning issue is homelessness in Kansas City, MO
To: Tom Tresser
From: Roger Warren
Global Situational Awareness of A.I. and where its headed
You can see the future first in San Francisco.
Over the past year, the talk of the town has shifted from $10 billion compute clusters to $100 billion clusters to trillion-dollar clusters. Every six months another zero is added to the boardroom plans. Behind the scenes, there’s a fierce scramble to secure every power contract still available for the rest of the decade, every voltage transformer that can possibly be procured. American big business is gearing up to pour trillions of dollars into a long-unseen mobilization of American industrial might. By the end of the decade, American electricity production will have grown tens of percent; from the shale fields of Pennsylvania to the solar farms of Nevada, hundreds of millions of GPUs will hum.
The AGI race has begun. We are building machines that can think and reason. By 2025/26, these machines will outpace college graduates. By the end of the decade, they will be smarter than you or I; we will have superintelligence, in the true sense of the word. Along the way, national security forces not seen in half a century will be un-leashed, and before long, The Project will be on. If we’re lucky, we’ll be in an all-out race with the CCP; if we’re unlucky, an all-out war.
Everyone is now talking about AI, but few have the faintest glimmer of what is about to hit them. Nvidia analysts still think 2024 might be close to the peak. Mainstream pundits are stuck on the wilful blindness of “it’s just predicting the next word”. They see only hype and business-as-usual; at most they entertain another internet-scale technological change.
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【业务选择办理准则】
一、工作未确定，回国需先给父母、亲戚朋友看下文凭的情况，办理一份就读学校的毕业证【微信41543339】文凭即可
二、回国进私企、外企、自己做生意的情况，这些单位是不查询毕业证真伪的，而且国内没有渠道去查询国外文凭的真假，也不需要提供真实教育部认证。鉴于此，办理一份毕业证【微信41543339】即可
三、进国企，银行，事业单位，考公务员等等，这些单位是必需要提供真实教育部认证的，办理教育部认证所需资料众多且烦琐，所有材料您都必须提供原件，我们凭借丰富的经验，快捷的绿色通道帮您快速整合材料，让您少走弯路。
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
留信网服务项目：
1、留学生专业人才库服务（留信分析）
2、国（境）学习人员提供就业推荐信服务
3、留学人员区块链存储服务
→ 【关于价格问题（保证一手价格）】
我们所定的价格是非常合理的，而且我们现在做得单子大多数都是代理和回头客户介绍的所以一般现在有新的单子 我给客户的都是第一手的代理价格，因为我想坦诚对待大家 不想跟大家在价格方面浪费时间
对于老客户或者被老客户介绍过来的朋友，我们都会适当给一些优惠。
选择实体注册公司办理，更放心，更安全！我们的承诺：客户在留信官方认证查询网站查询到认证通过结果后付款，不成功不收费！
一比一原版(UCSB文凭证书)圣芭芭拉分校毕业证如何办理
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【我们承诺采用的是学校原版纸张（纸质、底色、纹路），我们拥有全套进口原装设备，特殊工艺都是采用不同机器制作，仿真度基本可以达到100%，所有工艺效果都可提前给客户展示，不满意可以根据客户要求进行调整，直到满意为止！】
【业务选择办理准则】
一、工作未确定，回国需先给父母、亲戚朋友看下文凭的情况，办理一份就读学校的毕业证【微信176555708】文凭即可
二、回国进私企、外企、自己做生意的情况，这些单位是不查询毕业证真伪的，而且国内没有渠道去查询国外文凭的真假，也不需要提供真实教育部认证。鉴于此，办理一份毕业证【微信176555708】即可
三、进国企，银行，事业单位，考公务员等等，这些单位是必需要提供真实教育部认证的，办理教育部认证所需资料众多且烦琐，所有材料您都必须提供原件，我们凭借丰富的经验，快捷的绿色通道帮您快速整合材料，让您少走弯路。
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
留信网服务项目：
1、留学生专业人才库服务（留信分析）
2、国（境）学习人员提供就业推荐信服务
3、留学人员区块链存储服务
→ 【关于价格问题（保证一手价格）】
我们所定的价格是非常合理的，而且我们现在做得单子大多数都是代理和回头客户介绍的所以一般现在有新的单子 我给客户的都是第一手的代理价格，因为我想坦诚对待大家 不想跟大家在价格方面浪费时间
对于老客户或者被老客户介绍过来的朋友，我们都会适当给一些优惠。
选择实体注册公司办理，更放心，更安全！我们的承诺：客户在留信官方认证查询网站查询到认证通过结果后付款，不成功不收费！
办(uts毕业证书)悉尼科技大学毕业证学历证书原版一模一样
原版一模一样【微信：741003700 】【(uts毕业证书)悉尼科技大学毕业证学历证书】【微信：741003700 】学位证，留信认证（真实可查，永久存档）offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原海外各大学 Bachelor Diploma degree, Master Degree Diploma
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问Q/微741003700
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
一比一原版(Coventry毕业证书)考文垂大学毕业证如何办理
毕业原版【微信:41543339】【(Coventry毕业证书)考文垂大学毕业证】【微信:41543339】成绩单、外壳、offer、留信学历认证（永久存档真实可查）采用学校原版纸张、特殊工艺完全按照原版一比一制作（包括：隐形水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠，文字图案浮雕，激光镭射，紫外荧光，温感，复印防伪）行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备，十五年致力于帮助留学生解决难题，业务范围有加拿大、英国、澳洲、韩国、美国、新加坡，新西兰等学历材料，包您满意。
【我们承诺采用的是学校原版纸张（纸质、底色、纹路），我们拥有全套进口原装设备，特殊工艺都是采用不同机器制作，仿真度基本可以达到100%，所有工艺效果都可提前给客户展示，不满意可以根据客户要求进行调整，直到满意为止！】
【业务选择办理准则】
一、工作未确定，回国需先给父母、亲戚朋友看下文凭的情况，办理一份就读学校的毕业证【微信41543339】文凭即可
二、回国进私企、外企、自己做生意的情况，这些单位是不查询毕业证真伪的，而且国内没有渠道去查询国外文凭的真假，也不需要提供真实教育部认证。鉴于此，办理一份毕业证【微信41543339】即可
三、进国企，银行，事业单位，考公务员等等，这些单位是必需要提供真实教育部认证的，办理教育部认证所需资料众多且烦琐，所有材料您都必须提供原件，我们凭借丰富的经验，快捷的绿色通道帮您快速整合材料，让您少走弯路。
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
留信网服务项目：
1、留学生专业人才库服务（留信分析）
2、国（境）学习人员提供就业推荐信服务
3、留学人员区块链存储服务
→ 【关于价格问题（保证一手价格）】
我们所定的价格是非常合理的，而且我们现在做得单子大多数都是代理和回头客户介绍的所以一般现在有新的单子 我给客户的都是第一手的代理价格，因为我想坦诚对待大家 不想跟大家在价格方面浪费时间
对于老客户或者被老客户介绍过来的朋友，我们都会适当给一些优惠。
选择实体注册公司办理，更放心，更安全！我们的承诺：客户在留信官方认证查询网站查询到认证通过结果后付款，不成功不收费！
University of New South Wales degree offer diploma Transcript
澳洲UNSW毕业证书制作新南威尔士大学假文凭定制Q微168899991做UNSW留信网教留服认证海牙认证改UNSW成绩单GPA做UNSW假学位证假文凭高仿毕业证申请新南威尔士大学University of New South Wales degree offer diploma Transcript
一比一原版(Glasgow毕业证书)格拉斯哥大学毕业证如何办理
毕业原版【微信:41543339】【(Glasgow毕业证书)格拉斯哥大学毕业证】【微信:41543339】成绩单、外壳、offer、留信学历认证（永久存档真实可查）采用学校原版纸张、特殊工艺完全按照原版一比一制作（包括：隐形水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠，文字图案浮雕，激光镭射，紫外荧光，温感，复印防伪）行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备，十五年致力于帮助留学生解决难题，业务范围有加拿大、英国、澳洲、韩国、美国、新加坡，新西兰等学历材料，包您满意。
【我们承诺采用的是学校原版纸张（纸质、底色、纹路），我们拥有全套进口原装设备，特殊工艺都是采用不同机器制作，仿真度基本可以达到100%，所有工艺效果都可提前给客户展示，不满意可以根据客户要求进行调整，直到满意为止！】
【业务选择办理准则】
一、工作未确定，回国需先给父母、亲戚朋友看下文凭的情况，办理一份就读学校的毕业证【微信41543339】文凭即可
二、回国进私企、外企、自己做生意的情况，这些单位是不查询毕业证真伪的，而且国内没有渠道去查询国外文凭的真假，也不需要提供真实教育部认证。鉴于此，办理一份毕业证【微信41543339】即可
三、进国企，银行，事业单位，考公务员等等，这些单位是必需要提供真实教育部认证的，办理教育部认证所需资料众多且烦琐，所有材料您都必须提供原件，我们凭借丰富的经验，快捷的绿色通道帮您快速整合材料，让您少走弯路。
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
留信网服务项目：
1、留学生专业人才库服务（留信分析）
2、国（境）学习人员提供就业推荐信服务
3、留学人员区块链存储服务
→ 【关于价格问题（保证一手价格）】
我们所定的价格是非常合理的，而且我们现在做得单子大多数都是代理和回头客户介绍的所以一般现在有新的单子 我给客户的都是第一手的代理价格，因为我想坦诚对待大家 不想跟大家在价格方面浪费时间
对于老客户或者被老客户介绍过来的朋友，我们都会适当给一些优惠。
选择实体注册公司办理，更放心，更安全！我们的承诺：客户在留信官方认证查询网站查询到认证通过结果后付款，不成功不收费！
The Building Blocks of QuestDB, a Time Series Database
Talk Delivered at Valencia Codes Meetup 2024-06.
Traditionally, databases have treated timestamps just as another data type. However, when performing real-time analytics, timestamps should be first class citizens and we need rich time semantics to get the most out of our data. We also need to deal with ever growing datasets while keeping performant, which is as fun as it sounds.
It is no wonder time-series databases are now more popular than ever before. Join me in this session to learn about the internal architecture and building blocks of QuestDB, an open source time-series database designed for speed. We will also review a history of some of the changes we have gone over the past two years to deal with late and unordered data, non-blocking writes, read-replicas, or faster batch ingestion.
一比一原版(Harvard毕业证书)哈佛大学毕业证如何办理
毕业原版【微信:41543339】【(Harvard毕业证书)哈佛大学毕业证】【微信:41543339】成绩单、外壳、offer、留信学历认证（永久存档真实可查）采用学校原版纸张、特殊工艺完全按照原版一比一制作（包括：隐形水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠，文字图案浮雕，激光镭射，紫外荧光，温感，复印防伪）行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备，十五年致力于帮助留学生解决难题，业务范围有加拿大、英国、澳洲、韩国、美国、新加坡，新西兰等学历材料，包您满意。
【我们承诺采用的是学校原版纸张（纸质、底色、纹路），我们拥有全套进口原装设备，特殊工艺都是采用不同机器制作，仿真度基本可以达到100%，所有工艺效果都可提前给客户展示，不满意可以根据客户要求进行调整，直到满意为止！】
【业务选择办理准则】
一、工作未确定，回国需先给父母、亲戚朋友看下文凭的情况，办理一份就读学校的毕业证【微信41543339】文凭即可
二、回国进私企、外企、自己做生意的情况，这些单位是不查询毕业证真伪的，而且国内没有渠道去查询国外文凭的真假，也不需要提供真实教育部认证。鉴于此，办理一份毕业证【微信41543339】即可
三、进国企，银行，事业单位，考公务员等等，这些单位是必需要提供真实教育部认证的，办理教育部认证所需资料众多且烦琐，所有材料您都必须提供原件，我们凭借丰富的经验，快捷的绿色通道帮您快速整合材料，让您少走弯路。
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
留信网服务项目：
1、留学生专业人才库服务（留信分析）
2、国（境）学习人员提供就业推荐信服务
3、留学人员区块链存储服务
→ 【关于价格问题（保证一手价格）】
我们所定的价格是非常合理的，而且我们现在做得单子大多数都是代理和回头客户介绍的所以一般现在有新的单子 我给客户的都是第一手的代理价格，因为我想坦诚对待大家 不想跟大家在价格方面浪费时间
对于老客户或者被老客户介绍过来的朋友，我们都会适当给一些优惠。
选择实体注册公司办理，更放心，更安全！我们的承诺：客户在留信官方认证查询网站查询到认证通过结果后付款，不成功不收费！
一比一原版(GWU,GW文凭证书)乔治·华盛顿大学毕业证如何办理
毕业原版【微信:176555708】【(GWU,GW毕业证书)乔治·华盛顿大学毕业证】【微信:176555708】成绩单、外壳、offer、留信学历认证（永久存档真实可查）采用学校原版纸张、特殊工艺完全按照原版一比一制作（包括：隐形水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠，文字图案浮雕，激光镭射，紫外荧光，温感，复印防伪）行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备，十五年致力于帮助留学生解决难题，业务范围有加拿大、英国、澳洲、韩国、美国、新加坡，新西兰等学历材料，包您满意。
【我们承诺采用的是学校原版纸张（纸质、底色、纹路），我们拥有全套进口原装设备，特殊工艺都是采用不同机器制作，仿真度基本可以达到100%，所有工艺效果都可提前给客户展示，不满意可以根据客户要求进行调整，直到满意为止！】
【业务选择办理准则】
一、工作未确定，回国需先给父母、亲戚朋友看下文凭的情况，办理一份就读学校的毕业证【微信176555708】文凭即可
二、回国进私企、外企、自己做生意的情况，这些单位是不查询毕业证真伪的，而且国内没有渠道去查询国外文凭的真假，也不需要提供真实教育部认证。鉴于此，办理一份毕业证【微信176555708】即可
三、进国企，银行，事业单位，考公务员等等，这些单位是必需要提供真实教育部认证的，办理教育部认证所需资料众多且烦琐，所有材料您都必须提供原件，我们凭借丰富的经验，快捷的绿色通道帮您快速整合材料，让您少走弯路。
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
7:个人信誉贷款加10分
8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
留信网服务项目：
1、留学生专业人才库服务（留信分析）
2、国（境）学习人员提供就业推荐信服务
3、留学人员区块链存储服务
→ 【关于价格问题（保证一手价格）】
我们所定的价格是非常合理的，而且我们现在做得单子大多数都是代理和回头客户介绍的所以一般现在有新的单子 我给客户的都是第一手的代理价格，因为我想坦诚对待大家 不想跟大家在价格方面浪费时间
对于老客户或者被老客户介绍过来的朋友，我们都会适当给一些优惠。
选择实体注册公司办理，更放心，更安全！我们的承诺：客户在留信官方认证查询网站查询到认证通过结果后付款，不成功不收费！
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Database keys
- 1. Database Keys Presented by Rahul Mishra
- 2. Database keys Keys are very important part of Relational database. They are used to establish and identify relation between tables. They also ensure that each record within a table can be uniquely identified by combination of one or more fields within a table.
- 3. Types:- 1. Primary Key 2. Candidate Key 3. Alternate Key 4. Composite 5. Super Key 6. Foeign Key
- 4. 1. Super Key Emp_code Name Address Dept_ID It is an attribute or an set of attribute whose combined value uniquely identifies a tuple within a relation. {Emp_code, Name, Address, Dept_ID}, {Emp_code, Name, Address}, {Name, Address}, {Emp_code}, etc.
- 5. 2. Candidate Key Emp_code Name Address Dept_ID It is a minimal super key i.e., a super key which does not have any proper subset which is also a super key. {Emp_code} and {Name, Address}
- 6. 3. Primary Key Emp_code Name Address Dept_ID A candidate key which is actually chosen by database designer as the means of uniquely identifying the tuple within a relation. {Emp_code}
- 7. 4. Alternate Key Emp_code Name Address Dept_ID All candidate keys which are not chosen as a primary key is called an alternate key. {Name, Address}
- 8. 5. Composite Key Emp_code Name Address Dept_ID A primary key formed by combination of one or more attributes. {Name, Address}
- 9. 6. Foreign Key Emp_code Name Address Dept_ID A foreign key is a field (or collection of fields) in one table that uniquely identifies a row of another table or the same table. Department Dept_ID Dept_Name Employee Dept_ID – Primary Key in Department Table Foreign Key in Employee Table
- 10. Thank You! Here is a potato for you!!!