Components of a Query
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Components of a Query

Components of a Query

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Components of a Query

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By definition, a query is much the same as a question. In the case of database queries, a user is asking their database a question. Computer programs use languages that we, as humans do not ordinarily use in our daily lives. In this case Query Wizard acts as our interpreter. The Query Wizard interpreter allows questions to be asked in a language that both the user and their database will understand.

 

Each Query may consist of one or more questions, logically connected with an AND or an OR logical operator. In order to complete a valid "computer" question Query Wizard must collect three components of information: Field, Operator and Value. Given these three components, Query Wizard will construct a meaningful question.

 

 

Field

The Field is generally representative of information contained within in the database for which the developer has made available. The field is therefore considered the subject of the question or what you would like to learn about. A few examples of fields would be Account Balance, Last Name or Zip Code.

 

 

Operator

The Operator represents the comparison to be made between the Field and Value. Due to the nature of the value, operator selections for numbers are limited when compared to those for text. For example the most common numeric operators are Greater Than, Less Than or Equal To. The nature of text operators allow for such comparisons as Contains and Begins With. The Operation Selection guide discusses these issues in greater detail.

 

 

Value

The Value will be compared (via the operator) to the field in your database. The value entry is the way you wish to describe the subject (field) of the question. In essence the value describes the trait the field should have (or not have). Query Wizard offers many useful features to assist the user with their value consideration.