Progress
Language Reference
NE or <> Operator
Compares two expressions and returns a TRUE value if they are not equal.
If characters are being compared, the character values are used to index into the current collation table so that the sort value of the characters are used in the comparison.
SYNTAX
expression
A constant, field name, variable name, or expression. The expressions on either side of the NE or must be of the same data type.
EXAMPLEThis procedure displays information for all items that appear in the catalog. (The cat-page field is not equal to the unknown value or 0).
NOTES
- If one of the expressions has an unknown value (?) and the other does not, the result is TRUE. If both are unknown, the result is FALSE. For SQL, however, if one or both expressions is unknown, then the result is unknown.
- You can compare character strings with NE. Most character comparisons are case insensitive in Progress. That is, all characters are converted to uppercase prior to comparisons. However, it is possible to define fields and variables as case sensitive (although it is not advised, unless strict ANSI SQL adherence is required). If either expression is a field or variable defined as case sensitive, the comparison is case sensitive and “Smith” does not equal “smith” .
- Characters are converted to their sort code values for comparison. Using the default collation table, all uppercase letters sort before all lowercase letters (for example, a is greater than Z, but less than b.) Note also that in character code uppercase A is less than [ , \ , ^ , _, and ’ , but lowercase a is greater than these.
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