A database table usually has a(n) _______________________ that uniquely identifies each row in the table.

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When considering what a database table typically includes to uniquely identify each row, several options fall into different categories.
Option 1: 'primary key' — This is the standard mechanism used to ensure each row can be uniquely identified. A primary key is a column (or set of columns) with a unique constraint that differentiates every record. In most database designs, defining a primary key is central to data integrity and helps with efficient lookups, joins, and referencing in foreign keys.
Option 2: 'number' — Simply labeling a column as a number does not guarantee uniqueness. A numeric column can contain duplicates unless a uniqueness constraint or primary key is applied, so it does not by itself identify each row uniquely.
Option 3: 'label' — A label is typically a descriptive string and is not inherently unique. Depending on the data modeling, labels may repeat across rows (e.g., category names or tags), so relying on a label to identify a row would be unreliable.
Option 4: 'index' — An index improves search performance and can be created on one or more columns, but an index itself is not automatically guaranteed to be unique unless defined as a UNIQUE index or part of a primary key. Many indexes allow duplicate values, which means they do not guarantee unique row identification on their own.
In summary, the primary key is the intended mechanism to uniquely identify each row, while the other options describe different schema or performance features that do not inherently provide uniqueness across all rows.

BZAN2021.05|.06 Fall 2025 Coding for Business [Karpovsky] Reading Quiz: Organizing Data

A database table usually has a(n) _______________________ that uniquely identifies each row in the table.

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Question at position 11 In ERDs, the primary key isAn attribute that cannot be modified after it is setAn attribute that uniquely identifies each record in a database tableA graphical symbol indicating the connection between entitiesA set of optional attributes linked to an entity

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