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What database fields would be the most suitable to use as primary key?
Wiki User
∙ 13y ago
National Insurance number as everyone's is individual to them, no two NI numbers match
Wiki User
∙ 13y ago
Generally, the most suitable fields to use as a primary key in a database are those that are unique and have a simple and stable value. Common choices include a unique identifier field, such as an auto-incrementing integer or GUID, or a combination of multiple fields that together uniquely identify each record. It is also important to choose a field or combination of fields that do not change frequently to maintain data integrity.
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What is a primary key in relational databases?
A primary key is a set of one or more attributes that can uniquely identify tuples within the relation.A Primary Key is made up of one or more fields or columns that are used to uniquely identify a record or row in a table. No two records can have the same primary key and the database manager will not allow that to happenPrimary key consists of column or columns whose value uniquely identifies a row.Following are the key feature of primary keyIt can't be nullThere can ONLY be one primary key defined on a single table.A database designer choose this key to identifying unique records within a table. its values must not change. a primary key tells you the difference between James smith and another James smith because one has a different number than the other.The primary key is the field, or combination of fields, that uniquely identify each record in a table. It is usually the primary key that is stored in other tables (in which case it is called a "foreign key"), to find the record in the specified table. For example, a client might be identified by a field ClientId, which uniquely identifies each client. In the client table, this field would be called the "primary key"; if used in other tables to refer to a client, it is called a "foreign key".We can uniquely identify the database by which attribute or set of attributes that is called the PRIMARY KEY.it's basically a unique reference or ID (usually a number). You may need to create this in your database, or your dataset may already contain a unique ID field.In a database , the primary key field defines the field that is unique and not null. Primary key is used to uniquely define a key.It is used to uniquely identify each row in a table. The values must be unique and can not simply have NOT NULL.To uniquely identify a tuple or row in database , primary key must be used. a primary key is used to uniquely identify a tuple.A primary key is the unique identifier for a row in a database table. It is formed into a unique index constraint, so that access to the row in question can be quick. It is usually preferred by the optimizer as the primary join predicate. Presence of the primary key is usually a prerequiste for building a dynaset query, as opposed to a snapshot query, or for making an updateable view joining more than one table.the powerful in a releation database management system such as MICROSOFT ACCESS from the ability to quikly find and bring together information stored in separate tables. in order for MICROSOFT ACCESS to work most efficiently each table in your database should include a field or set of fields that uniquely identifies each individual record stored in table. this often a unique idnetification number,such as an employee ID number or serial number. IN DATABASE TERMINOLOGY, this information is called of the table. MICROSOFT ACCESS uses primary key field to quikly associate data from multiple tables and bring the data together for you. make sure the values in this field will always be different for each record MICROSOFT ACCESS doesnt allow duplicate values in
When would you use a Primary Key and when would you not?
A primary key is a key that is unique. A primary key is used to identify a record uniquely. There is not any particular case to not have a primary key . If you want to identify your records you should have a primary key or a surrogate key(as an alternative to it) .In reality, you should always have a primary key. A primary key is there to uniquely identify each record, as it is like other elements would be duplicated. If you had a very large amount of names of people, then it is highly likely that the same firstname or same surname or even the same full name will come up more than once. Having a primary key distinguishes them as each primary key has to be unique.Situations where you might not use it is where you have a very defined set of values where there is guaranteed to be no duplicates, like a database that has the 12 months of the year or a list of regions that all have different names. You still could make them primary keys, but in the case of the months, it would change them into alphabetical order, which you would not want, so that would be another reason for not using a primary key. To keep them in order, you could add another field, with the values from 1 to 12 and use that field as the primary key.
How would you find a certain product number in a database?
Typically you would do a SELECT statement for the table that contains the product list. The details depend on the names of the table, of the fields, and of the information you know; for example if you know that the product description is "xyz", you could issue a command similar to the following:select * from ProductList where ProductName = "xyz";
What are the advantage of using fixed length fields instead of variable length fields in a database?
A fixed length field is one which contains a set number of characters.With fixed length fields, the fields may need to be padded out to the right length, eg with characters.eg If a Surname field is set at 10 characters then the name SIMPSON would need 3 s added on to the end of it.Advantage - Every record is the same size, so it is possible for the computer to calculate exactly where each record starts in the file and therefore it is quicker for the computer to find a particular record.
Is this true or false did women only work at home and thay never worked in the fields?
Women would work at home and rarely work on fields
What database fields would be the most suitable to use as a primary key Student Name?
It is recommended to use a unique identifier such as a student ID number as a primary key instead of the student name. This is because names are not always unique and can change, while an ID is a reliable and stable way to uniquely identify each student's record in the database.
What are the fields that you would expect to find in a database for a shop selling computer games?
List the fields that you would expect to find in a database for a shop selling computer games.
What is an unlikely primary key?
A first name, a surname, a date of birth, and an address are just some examples of fields that would not be used as primary keys. Lots of people will have the same name or same date of birth and you could have people in your database that are living at the same address, so they are likely to be duplicated and so none of those fields should be used as primary key fields.
Why do you require a RegNo field in MS-access when you already have RollNo field?
That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.That question cannot really be answered, as it is down to the data you have and the database you are trying to design. You may well need these fields and have one as a primary key and have another field unique. To properly design a database, a lot of thought has to go into it, especially if there is more than one table and there are relationships. Even for one table you would work out what fields you need and how you design them. So you may have a requirement for both of those fields. It is your design, not Access itself, that decides what fields you need.
What fields would a doctor surgery might be in the database?
some of the fields a doctor surgery database would have are:Patient ID numberfirst namelast namehouse number/namestreet namecity/townpost codedoctors last name
What would a developer of a relational database call a record?
A developer of a relational database would call a record a "row" in database terminology. This term typically refers to a single entry in a database table that contains a set of related data fields.
What type of application would you use to store data in an organized manner using fields and records?
Database
What is the features homogeneous database?
Its primary feature would be setting up a database link between Oracle and another database such as SQL Server. Homogeneous database links are set up as new listeners which can be referred to in your TNSnames.
Is it true in access that examples of database field names might be first name last name address and phone?
Yes, in an Access database, typical field names for a table storing contact information could include "First Name," "Last Name," "Address," and "Phone." These field names help organize and categorize the data within the database, making it easier to manage and retrieve information.
Why do you need common fields in a database?
A common field is a field of data that is shared among all forms in a database. Without them, it would be difficult and/or time-consuming to create other forms.
What is a field in a database that contains formulas or functions in Excel?
In a database a field with a formula is called a calculated field. A calculated field should actually be in a table, as it can be calculated from data in other fields in the table, so it normally only appears in queries, reports and forms. In a spreadsheet it would just be a calculation.
What is a field that might be used in a database about students?
A field that might be used in a database about students is "student ID," which is a unique identifier for each student in the database.
