Match the words with their synonyms.

data; 2) include; 3) model; 4) assist; 5) start; 6) alter; 7) calculate

count; b) information; c) change; d) involve; e) pattern; f) help; g) begin

Read the sentences choosing the correct word in bold type.

Give the Russian equivalents.

1) identifying relationships; 2) certain data entities; 3)improved response time; 4)lower operating cost; 5) reduced storage space; 6) key considerations; 7) to meet information needs

5. Find the answers to the questions:

1. What should one determine in organizing data in a database?

2. What does physical database design start from?

3. What does the logical design of a database show?

4. Why may the logical database design need to be altered?

5. What must the person identified to fine-tune the physical design have?

Text B: Database Models

The structure of the relationships in most databases follows one of three logical models: hierarchical, network, and relational. Hierarсhical and network models are still being used today, but relational models are the most popular. It is important to remember that the records represented in the models are actually linked or related logically to one another. These links dictate the way users can access data with application programs. Because the different models involve different links between data, each model has unique advantages and disadvantages.

Relational models have become the most popular database models, and use of these models will increase in the future. The relational model describes data using a standard tabular format. In a database structured according to the relational model, all data elements are placed in two-dimensional tables, called relations, which are the logical equivalent of files. The tables in relational databases organize data in rows and columns, simplifying data access and manipulation. It is normally easier for managers to understand the relational model than the hierarchical and network models.

In the relational model, each row of table represents a data entity, with the columns of the table representing attributes. Each attribute can take on only certain values. The allowable values for these attributes are called the domain. The domain for a particular attribute indicates what values can be placed in each of the columns of the relational table.

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Text A: Data Modeling	\|	Mark the following statements as true or false.

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