Information about Column (database)
In the context of a relational database table, a column is a set of data values of a particular simple type, one for each row of the table.[1] The columns provide the structure according to which the rows are composed.
The term field is often used interchangeably with column, although many consider it more correct to use field (or field value) to refer specifically to the single item that exists at the intersection between one row and one column.
For example, a table that represents companies might have the following columns:
Debt, AIDS, Trade in Africa (or DATA) is a multinational non-government organization founded in January 2002 in London by U2's Bono along with Bobby Shriver and activists from the Jubilee 2000 Drop
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In mathematics, a tuple is a finite sequence (also known as an "ordered list") of objects, each of a specified type. A tuple containing n objects is known as an "n-tuple".
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The term field is often used interchangeably with column, although many consider it more correct to use field (or field value) to refer specifically to the single item that exists at the intersection between one row and one column.
For example, a table that represents companies might have the following columns:
- ID (integer identifier, unique to each row)
- Name (text)
- Address line 1 (text)
- Address line 2 (text)
- City (integer identifier, drawn from a separate table of cities, from which any state or country information would be drawn)
- Postal code (text)
- Industry (integer identifier, drawn from a separate table of industries)
- etc.
| Row 1 Column 1 | Row 1 Column 2 |
| Row 2 Column 1 | Row 2 Column 2 |
| Row 3 Column 1 | Row 3 Column 2 |
See also
References
1. ^ The term "column" also has equivalent application in other, more generic contexts. See e.g., Flat file database, Table (information).
A relational database is a database that conforms to the relational model, and refers to a database's data and schema (the database's structure of how that data is arranged).
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table is a set of data elements (values) that is organized using a model of horizontal rows and vertical columns. The columns are identified by name, and the rows are identified by the values appearing in a particular column subset which has been identified as a candidate key.
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- For other uses, see Data (disambiguation).
Debt, AIDS, Trade in Africa (or DATA) is a multinational non-government organization founded in January 2002 in London by U2's Bono along with Bobby Shriver and activists from the Jubilee 2000 Drop
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In programming languages a data type defines a set of values and the allowable operations on those values[1]. For example, in the Java programming language, the "int" type represents the set of 32-bit integers ranging in value from -2,147,483,648 to 2,147,483,647, and
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In the context of a relational database, a row—also called a record or tuple—represents a single, implicitly structured data item in a table. In simple terms, a database table can be thought of as consisting of rows and columns or fields.
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In computer science, data that has several parts can be divided into fields. For example, a computer may represent today's date as three distinct fields: the day, the month and the year.
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In relational databases, a relvar is an abbreviation for "relation variable". The term is used in the well-known database textbook by C.J. Date to differentiate between a variable that contains a relation and the relation itself.
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For the musical term, see .
In mathematics, a tuple is a finite sequence (also known as an "ordered list") of objects, each of a specified type. A tuple containing n objects is known as an "n-tuple".
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In the context of a relational database, a row—also called a record or tuple—represents a single, implicitly structured data item in a table. In simple terms, a database table can be thought of as consisting of rows and columns or fields.
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flat file database describes any of various means to encode a data model (most commonly a table) as a plain text file.
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Flat files
A flat file is a file that contains records, and in which each record is specified in a single line...... Click the link for more information.
table is both a mode of visual communication and a means of arranging data. The use of tables is pervasive throughout all communication, research and data analysis. Tables appear in print media, handwritten notes, computer software, architectural ornamentation, traffic signs and
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