Let's examine the notion of a simple condition in detail.
A simple condition is a condition (limitation) imposed on the value of one of table fields and as a rule consisting of three parts – field name, relation and possibly operands – constants.
We'll demonstrate simple conditions for some examples given above:
the field value “Street” is equal to the string “Sea Lane”: the field name – “Street”, relation –“equal”, operand – “Sea Lane”;
the field value “Is Municipal?” is equal to “true”: the field name – “Is Municipal?”, relation – “equal”, operand – “True”;
the field value “Number of Storeys” is not greater than two: field name – “Number of Storeys”, relation – “not greater”, operand – 2;
the field value “Date of Last Repair” should be referred to dates before 1994: field name – “Date of Last Repair”, relation – “before”, operand – 1.01.1994.
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