Relation conditions
A relation condition specifies the comparison of two operands. The relational operator that joins the two operands specifies the type of comparison. The relation condition is true if the specified relation exists between the two operands; the relation condition is false if the specified relation does not exist.
Syntax
operand-1  [ IS ]  [ NOT ]  { GREATER THAN               }                operand-2
                            { LESS THAN                  }
                            { EQUAL TO                   }
                            { >                          }
                            { <                          }
                            { <>                         }
                            { =                          }
                            { >=                         }
                            { <=                         }
                            { LIKE [ TRIMMED { LEFT  } ] }
                                             { RIGHT }
                                   [ CASE-INSENSITIVE  ]
                                   [ CASE-SENSITIVE    ]
                                   [ APPROX { numeric-literal-1   } ]
                                            { numeric-data-item-1 }
This additional syntax is supported when compiling with -cm:.
operand-1 { EQUALS        }  operand-2
          { IS UNEQUAL TO }
          { EXCEEDS       }
operand-1 and operand-2 may be either an arithmetic expression, a data name, or a literal.
When the LIKE operator is used, operand-2 identifies a regular expression.
After the APPROX clause an integer value must be specified, specifying the maximum number of allowed errors, computed according to the Levenshtein distance. The second operator in this case cannot be a regular expression, however it can contain the wildcard "?", any character, and "*", a sequence of 0 or more characters. "\" is the escape character, so that: "\*" becomes *, "\?" becomes "?" and "\\" becomes "\".