In relational model, a tuple is a?

In a relational model, a "tuple" refers to a "row of a table". In a relational database, data is organized into tables, which consist of rows and columns. Each row in a table represents a single instance of the entity or object that the table represents. For example, in a "Customers" table, each row would represent a single customer. A tuple is a single row within a table. It contains a collection of values, with each value representing a single attribute or column in the table. For example, a tuple in the "Customers" table might contain values for the customer's name, address, phone number, and email address. Tuples can be used to retrieve and manipulate data in a relational database. They are often used in conjunction with SQL (Structured Query Language) statements to select, update, or delete specific rows of data within a table. It's important to note that a tuple is not the same as a key of a table or a column of a table. A key is a column or combination of columns that uniquely identifies each row in a table, while a column is a vertical set of values within a table.