A field in the database refers to a column of the table. Each row in the data table is a "record", and each record contains all the information in this row; fields are smaller units than records, and a collection of fields constitutes a record. Each field describes a certain feature of the document, that is, data item, and has a unique field identifier recognized by computers.
We call each row in the table a "record", and each record contains all the information in this row, just like a certain record in the address book database. All personal information, but recorded in the database, does not have a special record name. The row number where it is located is often used to indicate which record it is. Fields are smaller units than records. A collection of fields forms a record. Each field describes a certain feature of the document, that is, a data item, and has a unique field identifier for computer recognition.
Field
(field)
A member that represents a variable associated with an object or class.
In the database, most of the time, the "columns" of the table are called "fields", and each field contains information about a certain topic. Just like in the "Address Book" database, "Name" and "Contact Number" are attributes common to all rows in the table, so these columns are called the "Name" field and "Contact Number" field.
But sometimes, the fields are not columns in the table. For example, as is used to calculate the contents of the column and "store" it in another field. For example: There is only column "ID" in a table "T", and the content is "int" value "1". Using "select id, id * 5 as abc from T", the result is
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