Relation operators recognized are

       EQ,  NE,  LT,  LE,  GT,  GE,
       FROM ....TO                           SELECTS IF WITHIN A RANGE
       NOT-FROM ..... TO                SELECTS IF OUTSIDE THE GIVEN RANGE.
       CONTAINS                             LOOKS FOR A SPECIFIC VALUE.
       OMITS                                      EXCLUDES A SPECIFIC VALUE.

NOTE
1.  CONTAINS  AND  OMITS  CAN ONLY BE USED WITH  ALPHA FIELDS.
 2.  FOR  CONTAINS , IF THE VALUE IS FOUND THE RECORD  IS  SELECTED.
 3.  FOR  OMITS IF THE VALUE IS  FOUND, IT IS BYPASSED.

 EDITING OPTIONS AND MASKING.

 TABLE FILE  MAST
 PRINT FIRST_NAME LAST_NAME
 IF   FIRST_NAME IS  ‘A$*’
 END
 
THIS  SELECTS  ONLY THOSE RECORDS  WHOSE FIRST NAME BEGIN WITH  ‘A’ .
 THE  ‘$’ IS USED TO MASK OUT  THE  OTHER CONTENTS OF THE RECORD.
 IT CAN BE USED ANY WHERE.
 LIKE  ‘AB$$CD’
 ONLY THOSE   THAT HAVE  THEIR FIRST TWO CHARACTERS AS  AB AND  LAST  TWO AS CD WILL BE SELECTED.
 EDITING OPTIONS ARE USED TO CHANGE THE MANNER IN WHICH A FIELD IS  DISPLAYED.
 EG. SSN NUMBER  STORED AS  AN 9 DIGIT INTEGER.
 IF HOWEVER, IT IS TO BE DISPLAYED IN THE REPORT WITH HYPHENS, THEN
 EID/A11 = EDIT(EMP_ID,’999-999-999’)
 This creates a field (temporary) called EID, and EID is displayed in the report as
 123-456-789. The 9 in this case passes any value.

RECORDLIMIT.

USED AS :
IF RECORDLIMIT EQ n ( N > 0).
 Only the first n records will be read.
 Used primarily for testing.
 Selects only those records that meet all other screening conditions.
 

DEFINING   TEMPORARY  FIELDS .

 DEFINE FILE <filename>   [ADD]
 FIELDNAME1[/format] = expression;
 “
 “
 “
 FIELDNAME256[/format]=expression;
 END

 Where    fieldname  = 1 - 12 characters.
   format        =  Any Focus allowed format.
   Expression = Any value compatible with the format.
     Any  logical expression.
     Any arthetimic expression.
     ; ends the expression.

 The temporary fields defined in the TABLE request are local only for that request.
 If it desired to carry it over to another TABLE request, then ADD is used in the
 TABLE request where the previous fields are needed.
 They  can also be explicitly cleared by the CLEAR verb (instead of the ADD) ,
 however CLEAR is the default.

 Any number of  temporary fields can be derived  based on an actual field in the MFD.
 The only limitation is that the total DEFINEd fields in an TABLE  should not exceed 256.
 The temporary fields are treated as real fields residing in the database. Also they are treated
 as appended to the bottom of the segment in which the real field resides.
 Ex.

  DEFINE FILE  EMPLOYEE
   BIRTH_DATE/A6=EDIT(DOB,’$$99$$’) | EDIT(DOB,’$$$$99’) |         EDIT(DOB,’99$$$$’);
  END
 
  This defines a temporary field BIRTH_DATE.
  The’ | ‘symbol is for concatenation.
  A single ‘ | ‘ is for weak concatenation, whereas  ‘ || ‘ is for strong concatenation.
  In case of strong concatenation, the trailing spaces are removed.
  This above example can be used for  changing the format from YMD to MDY.
Temporary fields can also be DEFINEd in the MFD.
 
Rules for defining temporary fields in the MFD.
· A  DEFINE   statement in the MFD can only refer to a  field in it's own segment. Hence it is best to place a DEFINEd field  next to  the  actual  field  from which it is derived.
· A  DEFINEd  field  in the MFD   are available whenever  the data file is used,  and it is  treated
   as  just  another  stored  field , so it cannot be CLEARed  in the report request.
· A   temporary  field  cannot  be used  for  cross referencing (  in JOINs ).
 

EDIT
  EDIT changes the format from Alpha to Numeric and vice versa.

  NEW_EID/A9=EDIT(EID);

  If    EID  is defined in the MFD as  an I9  field NEW_EID is A9, and vice versa.
 
COMPUTE
  TABLE FILE EMPLOYEE
  SUM  CSAL
  COMPUTE BUDGET/A10=IF  CSAL GE 110000 THEN   ‘HIGH’
      ELSE  IF  CSAL  GE  ‘75000’ THEN ‘AVERAGE’
       ELSE  ‘LOW’;
  BY DEPT
  END
 

 DEPT            CURR_SAL     BUDGET
-------             -----------       ----------
 SOFTWARE    5000                 LOW
 HARDWARE   80000               HIGH
 TRG                 120000              AVERAGE

 Difference between COMPUTE  and  DEFINE
 
 COMPUTE <exp> . The expression is executed only at the control break,
  if sortfield exists, else after all the records are retrieved.
 

   EXTRACT  FILES

  TABLE FILE <filename>
    ...... report  request......
  ON  TABLE  HOLD  [ AS NEW FILE NAME]
  END

  HOLD  saves the data selected in the report request in a sequential file.
  Creates a MFD for the file.
  ? HOLD in the Focus prompt shows the HOLD FILE' s MFD.
  The contents of the HOLD file can subsequently be used  in another report request.
Click here to learn on  date formats in FOCUS and their usage.