Chapter 4-3: Specifying Statements
The Relational Component
The relational component (or relation) includes several abbreviations that correspond to a series of relational operators that are used when comparing the values of two fields, as follows:
LT (less than) checks if the value of a first-named field is less than that of a second field.
GT (greater than) checks if the value of a first-named field is greater than a second field.
LE (less than or equal to)checks if the value of a first-named field is less than or equal to a second field.
GE (greater than or equal to) checks if the value of a first-named field is greater than or equal to a second field.
EQ (equal to)checks if the value of a first-named field is equal to that of a second field.
NE (not equal to) checks if the value of a first-named field is not equal to that of a second field.
IN (includes)checks if a specified character string is included within the value of a field. For example, you could check to see if the letter string NOR is included in the CUSTOMER NAME field.
EX (excludes) checks if a specified character string is excluded from the value of a field. For example, you could check to see if the letter string NOR does not exist in the CUSTOMER NAME field.