The 
FATS matchcode commands create a full-text index with the content of your data tables or -files.
Every word and every number is incorporated into the index, an "inverted list" is generated.This index enables FATS to find each data record by specification of any terms in fractions of a second.
The following Microsoft Basic example demonstrates the use of the FATS matchcode commands:
PRINT "This program needs the extended version of FATS (FATSX.OBJ or FATSXO16.DLL)"
PRINT "It tests the 'MC', 'MB', 'MS' and 'MA' commands"
PRINT
PRINT "Up to version 6.0 of the basic compiler all strings were administered"
PRINT "in the data segment of the application. Starting from the version 7.0"
PRINT "the entire memory can be used by strings (compiler flag /Fs)."
PRINT
PRINT "To compile and link the test program, use ONE of the following methods:"
PRINT
PRINT " 1. METHOD: Linking FATS to the program"
PRINT
PRINT " BC TST2_ENG /Lp"
PRINT " LINK TST2_ENG fatsx.obj fats_mb6.obj"
PRINT
PRINT " or if you use Far-Strings:"
PRINT
PRINT " BC TST2_ENG /Lp /Fs"
PRINT " LINK TST2_ENG fatsx.obj fats_mb7.obj"
PRINT
PRINT " 2. METHOD: Calling the Dynamic Link Library"
PRINT
PRINT " BC TST2_ENG /Lp"
PRINT " LINK TST2_ENG fatsmb6d.obj fatsxo16.lib (call FATSXO16.DLL)"
PRINT
PRINT " or with Far-Strings:"
PRINT
PRINT " BC TST2_ENG /Lp /Fs"
PRINT " LINK TST2_ENG fatsmb7d.obj fatsxo16.lib"
PRINT
INPUT "Please press the [ENTER] key ...", X$
PRINT
REM -------> Activation of Network Operation
REM
REM FATS is standardly equiped for the network environment.
REM Nearly all commands can be executed both in single workstation
REM and network environment. With the "Y" Auto Refresh command you
REM determine the behavior of FATS accessing all index files.
REM Normally it is sufficient to apply this instruction one time at
REM the program start whereby the specified access mode will apply
REM to all coming opened files, i.e. they are accessed either with
REM network (Y\2) or single workstation access (Y\0).
CALL FATSBASIC("Y\2", ERRORCODE%, RECNO&, KEYLEN%)
REM -------> Open data file
PRINT "Opening data file ..."
OPEN "R", #1, "CUSTOMER.DAT", 128
FIELD #1, 1 AS DELETEDMARK$,_
5 AS CUSTID$,_
25 AS NAME$,_
25 AS JOB$,_
25 AS STREET$,_
5 AS ZIP$,_
20 AS CITY$
REM ========================================================================
REM Creating Matchcode Index
REM ========================================================================
REM -------> Creating Matchcode Index File
REM
REM With the command "MC" Create Matchcode File, the most important
REM query facilities are determined already while creating the
REM matchcode index file. With the search-group flag ("I#"), several
REM logically related data columns can be registered in a common index
REM so that a query to this index resp. search group extends automatically
REM over all these columns. A matchcode file manages up to 32 search
REM groups that can be used for joined queries (using the "AND"-operator).
REM
REM In this example the following search groups are defined:
REM
REM Search Group Fields
REM
REM I1 NAME
REM I2 JOB
REM I3 ZIP & CITY
REM
REM The syntax of the command string:
REM
REM szCmnd = "MC\{FileName}\{Flags}\{FileNo}\{Col1def}[\{Col2def}]"
REM
REM FileName Filename, perhaps with an additional path
REM (i.e. C:/DATA/CUSTOMER.FMS or CUSTOMER.FMS)
REM
REM Flags Reserved, not used at the moment
REM
REM FileNo File number
REM
REM Col#def Definition of data column # (flags, separated by comma).
REM The content of the corresponding data columns is transferred
REM the commands "MB", "MI" and "MD" later in the order determined
REM by this command.
REM
REM I# The content of the data column becomes part of search
REM group #. You can combine several columns into a logical
REM search group (e.g. first name, surname).
REM
REM C The content of the data column is edited for word overall
REM searching, i.e. a search for "motorca" e.g. finds
REM "motorcar" and "motor caravan".
REM
REM N Numbers are handled as words, i.e. during a search
REM according to "150", "12150" e.g. is also found.
REM
REM Further adjustments are possible and described in detail
REM in the user manual.
PRINT
PRINT "Creating matchcode index file ..."
CALL FATSBASIC("MC\CUSTOMER.FTS\\1\I1\I2\I3", ERRORCODE%, RECNO&, KEYLEN%)
IF ERRORCODE% <> 0 THEN
PRINT
PRINT "FATS errorcode: "; ERRORCODE%; " (command: MC)"
GOTO ENDE
END IF
REM -------> Insert text into the matchcode index
REM
REM After the matchcode file was generated, the content of the
REM data columns may be with the command "MB" Build Matchcode
REM inserted into the matchcode index. The position of the
REM data columns within the command string ("Col#data") corresponds
REM to that with the call of command Create Matchcode File ("MC")
REM determined definition.
REM
REM The syntax of the command string:
REM
REM szCmnd = "MB\{FileNo}\{RecNo}\{Col1data}[\{Col2data}[\{Col3data}]]"
REM
REM FileNo File number
REM
REM RecNo <> 0 Record- resp. id-number
REM == 0 Stop Build, no more records
REM
REM Col#data Content of data column #
REM
REM
REM The following sample program code indexes contents of the
REM entire data file within a loop:
PRINT
PRINT "Building matchcode index"
PRINT
INPUT "Please press the [ENTER] key ...", X$
CURRECNO& = 0
REM While indexing sequential data resources, the number specified
REM via "RecNo" should correspond to the physical record number
REM i.e. the first data record has number 1, the second record number 2..,
REM in the case of data records marked as deleted, the content of the
REM data columns is not specified ("MB\{FileNo}\{RecNo}").
REM
REM The Build Matchcode (MB) command demands an ascending number as a
REM "RecNo" argument i.e. the matchcode can not usually be indexed in
REM the logical order of an index-key.
REM The example program MCSORT.bas shows how an application
REM program might use the "MC" command to create the
REM matchcode index in sorted order.
DO
GET #1, CURRECNO& + 1
IF NOT EOF(1) THEN
CURRECNO& = CURRECNO& + 1
CMND$ = "MB\1\" + STR$(CURRECNO&)
IF DELETEDMARK$ = " " THEN
CMND$ = CMND$ + "\" + RTRIM$(NAME$)
CMND$ = CMND$ + "\" + RTRIM$(JOB$)
CMND$ = CMND$ + "\" + RTRIM$(ZIP$ + " " + CITY$)
END IF
CALL FATSBASIC(CMND$, ERRORCODE%, RECNO&, KEYLEN%)
IF ERRORCODE% <> 0 THEN
REM If an error occurred during the execution of the "MB" command,
REM the matchcode index file is already closed by FATS.
PRINT "FATS errorcode: "; ERRORCODE%; " (command: MB)"
EXIT DO
END IF
PRINT " "; NAME$; " --> RecNo "; CURRECNO&
ELSE
REM After the last record was inserted the creating process
REM has to be terminated with the command "MB\{FileNo}\0".
REM Because this command closes the matchcode index file you don't
REM have to do a close command.
CALL FATSBASIC("MB\1\0", ERRORCODE%, RECNO&, KEYLEN%)
END IF
LOOP WHILE NOT EOF(1)
IF CURRECNO& = 0 THEN
PRINT
PRINT "Error opening the file CUSTOMER.DAT"
PRINT "Please create the file using the test programs"
PRINT "TST0_ENG.BAS or TST1_ENG.BAS"
GOTO ENDE
END IF
REM ========================================================================
REM Matchcode Search
REM ========================================================================
REM -------> Open matchcode index file
REM
REM With the command "O" Open Indexfile you open an existing
REM matchcode index file with the opening flags defined with
REM the command "Y" Auto Refresh. After the file was opened
REM it can be accessed under the file number you specified.
CALL FATSBASIC("O\CUSTOMER.FTS\1", ERRORCODE%, RECNO&, KEYLEN%)
REM -------> Search in Search-Group 1 (NAME)
REM
REM The command "MS" Search in Matchcode searches the matchcode
REM index and fills the result set with the record- resp. ID-numbers
REM of data records which include the searched terms. If FATS finds
REM the requested terms, it returns the record- resp. ID-number of
REM the first hit in the "dwRecno" variable and a errorcode of 0.
REM The result set can then be read out with the browser commands
REM ("MA", "ME", "MN", "MP" ...).
REM
REM The syntax of the command string:
REM
REM szCmnd = "MS\{FileNo}\{Flags}\{Total}\{SearchGrp1}[\{SearchGrp2}...]"
REM
REM FileNo File number
REM
REM Flags The search procedure can be adjusted by the specification
REM of different flags. You find a description of the flags
REM in the command reference.
REM
REM Total Maximum number of hits in the result set:
REM
REM 0 All hits are set into the result set. This regulation
REM works very fast, however, no sorting occurs by means of
REM hit quality.
REM
REM >0 It is attempted to put the specified number of hits into
REM the result set. These hits are subjected to a sorting
REM concerning their quality and then put into one of
REM 7 sorting groups.
REM
REM SearchGrp# The in search group # searched terms.
REM
REM
REM Different FATS commands can be used for further processing
REM of the result table, depending on the program logic.
REM The following example prints all hits on the output device:
PRINT
PRINT "We now search for all customers with the first name Michael."
PRINT
INPUT "Please press the [ENTER] key ...", X$
PRINT
CMND$ = "MS\1\\0\michael"
DO
CALL FATSBASIC(CMND$, ERRORCODE%, RECNO&, KEYLEN%)
IF ERRORCODE% <> 0 THEN EXIT DO
GET #1, RECNO&
PRINT NAME$; " | "; JOB$
PRINT ZIP$; " "; CITY$; " (#"; RECNO&; ")"
PRINT
CMND$ = "MA\1\" + STR$(RECNO&)
LOOP WHILE NOT ERRORCODE%
REM The following browser commands are supported by FATS:
REM
REM "MF" - Get First Result
REM "ML" - Get Last Result
REM "MP" - Get Previous Result
REM "MN" - Get Next Result
REM "MA" - Get Next Result After
REM "ME" - Get Previous Result Before
REM --------> Joined search in Search-Groups 2 (JOB) and 3 (ZIP/CITY)
PRINT
PRINT "We are now doing a joined search over the search groups"
PRINT "2 (Job) and 3 (Zip, City) to find all people from nevada"
PRINT "who are related to the transportation industry."
PRINT
INPUT "Please press the [ENTER] key ...", X$
PRINT
CMND$ = "MS\1\\0\\trans\nev"
DO
CALL FATSBASIC(CMND$, ERRORCODE%, RECNO&, KEYLEN%)
IF ERRORCODE% <> 0 THEN EXIT DO
GET #1, RECNO&
PRINT NAME$; " | "; JOB$
PRINT ZIP$; " "; CITY$; " (#"; RECNO&; ")"
PRINT
CMND$ = "MA\1\" + STR$(RECNO&)
LOOP WHILE NOT ERRORCODE%
REM --------> Close matchcode index file
CALL FATSBASIC("K\1", ERRORCODE%, RECNO&, KEYLEN%)
ENDE:
CLOSE #1
© 2008 
GCS Software, Udo Gertz
