SET DELETED

SET DELETED

Toggle filtering of deleted records

Syntax

      SET DELETED on | OFF | <xlToggle>

Arguments

ON ignores deleted records.

OFF processes deleted records.

<xlToggle> is a logical expression that must be enclosed in parentheses. A value of true (.T.) is the same as ON, and a value of false (.F.) is the same as OFF.

Description

SET DELETED toggles automatic filtering of records marked for deletion in all work areas. When SET DELETED is ON, most commands ignore deleted records. If, however, you refer to a record by record number (GOTO or any command that supports the RECORD scope), the record is not ignored even if marked for deletion. Additionally, SET DELETED ON has no affect on INDEX or REINDEXing.

RECALL ALL honors SET DELETED and does not recall any records.

Notes

. Filtering deleted records in a single work area: To confine the filtering of deleted records to a particular work area, SELECT the work area, and then SET FILTER TO DELETED().

Examples

      .  This example illustrates the effect of using SET DELETED:

      USE Sales NEW
      ? LASTREC()                  // Result: 84
      //
      DELETE RECORD 4
      COUNT TO nCount
      ? nCount                     // Result: 84
      //
      SET DELETED ON
      COUNT TO nCount
      ? nCount                     // Result: 83

Seealso

DELETE, DELETED(), RECALL, SET FILTER

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DELETE

DELETE

Mark records for deletion

Syntax

      DELETE [<scope>] [WHILE <lCondition>]
             [FOR <lCondition>]

Arguments

<scope> is the portion of the current database file to DELETE. If a scope is not specified, DELETE acts only on the current record. If a conditional clause is specified, the default becomes ALL records.

WHILE <lCondition> specifies the set of records meeting the condition from the current record until the condition fails.

FOR <lCondition> specifies the conditional set of records to DELETE within the given scope.

Description

DELETE is a database command that tags records so they can be filtered with SET DELETED ON, queried with DELETED(), or physically removed from the database file with PACK. In addition, display commands such as LIST and DISPLAY identify deleted records with an asterisk (*) character. Once records are deleted, you can reinstate them by using RECALL. If you want to remove all records from a database file, use ZAP instead of DELETE ALL and PACK.

Any deleted record can be recalled as long as the PACK or ZAP command has not been issued. Once the PACK or ZAP command has been issued, the deleted data cannot be retrieved.

In a network environment, DELETE requires the current record be locked with RLOCK() if you are deleting a single record. If you are deleting several records, the current database file must be locked with FLOCK() or USEed EXCLUSIVEly. Refer to the “Network Programming” chapter in the Programming and Utilities Guide for more information.

Notes

. DELETE with SET DELETED ON: If the current record is deleted with SET DELETED ON, it will be visible until the record pointer is moved.

Examples

      .  This example demonstrates use of the FOR clause to mark a set
         of records for deletion:
      USE Sales INDEX Salesman NEW
      DELETE ALL FOR Inactive

Seealso

DBEVAL(), DELETED(), FLOCK(), PACK, RECALL, RLOCK()

PACK

PACK

Remove records marked for deletion from a database

Syntax

      PACK

Arguments

(This command has no arguments)

Description

This command removes records that were marked for deletion from the currently selected database. This command does not pack the contents of a memo field; those files must be packed via low-level fuctions.

All open index files will be automatically reindexed once PACK command has completed its operation. On completion, the record pointer is placed on the first record in the database.

Examples

      USE tests NEW INDEX tests
      DBGOTO( 10 )
      DELETE NEXT 10
      PACK
      USE

Compliance

Clipper

Seealso

DBEVAL(), DELETE, DELETED(), ZAP, RECALL

C5_RECALL

 RECALL
 Restore records marked for deletion
------------------------------------------------------------------------------
 Syntax

     RECALL [<scope>] [WHILE <lCondition>]
        [FOR <lCondition>]

 Arguments

     <scope> is the portion of the current database file to RECALL.  The
     default scope is the current record, or NEXT 1.  If a condition is
     specified, the default scope becomes ALL.

     WHILE <lCondition> specifies the set of records meeting the
     condition from the current record until the condition fails.

     FOR <lCondition> specifies the conditional set of records to RECALL
     within the given scope.

 Description

     RECALL is a database command that restores records marked for deletion
     in the current work area.  This is the inverse of the DELETE command.
     If DELETED is ON, RECALL can restore the current record or a specific
     record, if you specify a RECORD scope.  Note that once you PACK a
     database file, all marked records have been physically removed from the
     file and cannot be recovered.

     In a network environment, RECALLing the current record requires an
     RLOCK().  RECALLing several records requires an FLOCK() or EXCLUSIVE USE
     of the current database file.  Refer to the "Network Programming"
     chapter in the Programming and Utilities Guide for more information.

 Examples

     .  This examples show the results of RECALL:

        USE Sales NEW
        //
        DELETE RECORD 4
        ? DELETED()               // Result: .T.
        //
        RECALL
        ? DELETED()               // Result: .F.

 Files   Library is CLIPPER.LIB.

See Also: DELETE DELETED FLOCK() PACK RLOCK() SET DELETED

 

C5 Commands

 ?|??            Display one or more values to the console
 @...BOX         Draw a box on the screen
 @...CLEAR       Clear a rectangular region of the screen
 @...GET         Create a new Get object and display it
 @...PROMPT      Paint a menu item and define a message
 @...SAY         Display data at a specified screen or printer row and column
 @...TO          Draw a single- or double-line box
 ACCEPT*         Place keyboard input into a memory variable
 APPEND BLANK    Add a new record to the current database file
 APPEND FROM     Import records from a database (.dbf) file or ASCII text file
 AVERAGE         Average numeric expressions in the current work area
 CALL*           Execute a C or Assembler procedure
 CANCEL*         Terminate program processing
 CLEAR ALL*      Close files and release public and private variables
 CLEAR GETS      Release Get objects from the current GetList array
 CLEAR MEMORY    Release all public and private variables
 CLEAR SCREEN    Clear the screen and return the cursor home
 CLEAR TYPEAHEAD Empty the keyboard buffer
 CLOSE           Close a specific set of files
 COMMIT          Perform a solid-disk write for all active work areas
 CONTINUE        Resume a pending LOCATE
 COPY FILE       Copy a file to a new file or to a device
 COPY STRUCTURE  Copy the current .dbf structure to a new database (.dbf) file
 COPY STRU EXTE  Copy field definitions to a .dbf file
 COPY TO         Export records to a database (.dbf) file or ASCII text file
 COUNT           Tally records to a variable
 CREATE          Create an empty structure extended (.dbf) file
 CREATE FROM     Create a new .dbf file from a structure extended file
 DELETE          Mark records for deletion
 DELETE FILE     Remove a file from disk
 DELETE TAG      Delete a tag
 DIR*            Display a listing of files from a specified path
 DISPLAY         Display records to the console
 EJECT           Advance the printhead to top of form
 ERASE           Remove a file from disk
 FIND*           Search an index for a specified key value
 GO              Move the pointer to the specified identity
 INDEX           Create an index file
 INPUT*          Enter the result of an expression into a variable
 JOIN            Create a new database file by merging from two work areas
 KEYBOARD        Stuff a string into the keyboard buffer
 LABEL FORM      Display labels to the console
 LIST            List records to the console
 LOCATE          Search sequentially for a record matching a condition
 MENU TO         Execute a lightbar menu for defined PROMPTs
 NOTE*           Place a single-line comment in a program file
 PACK            Remove deleted records from a database file
 QUIT            Terminate program processing
 READ            Activate full-screen editing mode using Get objects
 RECALL          Restore records marked for deletion
 REINDEX         Rebuild open indexes in the current work area
 RELEASE         Delete public and private memory variables
 RENAME          Change the name of a file
 REPLACE         Assign new values to field variables
 REPORT FORM     Display a report to the console
 RESTORE         Retrieve memory variables from a memory (.mem) file
 RESTORE SCREEN* Display a saved screen
 RUN             Execute a DOS command or program
 SAVE            Save variables to a memory (.mem) file
 SAVE SCREEN*    Save the current screen to a buffer or variable
 SEEK            Search an order for a specified key value
 SELECT          Change the current work area
 SET ALTERNATE   Echo console output to a text file
 SET BELL        Toggle sounding of the bell during full-screen operations
 SET CENTURY     Modify the date format to include or omit century digits
 SET COLOR*      Define screen colors
 SET CONFIRM     Toggle required exit key to terminate GETs
 SET CONSOLE     Toggle console display to the screen
 SET CURSOR      Toggle the screen cursor on or off
 SET DATE        Set the date format for input and display
 SET DECIMALS    Set the number of decimal places to be displayed
 SET DEFAULT     Set the CA-Clipper default drive and directory
 SET DELETED     Toggle filtering of deleted records
 SET DELIMITERS  Toggle or define GET delimiters
 SET DESCENDING  Change the descending flag of the controlling order
 SET DEVICE      Direct @...SAYs to the screen or printer
 SET EPOCH       Control the interpretation of dates with no century digits
 SET ESCAPE      Toggle Esc as a READ exit key
 SET EXACT*      Toggle exact matches for character strings
 SET EXCLUSIVE*  Establish shared or exclusive USE of database files
 SET FILTER      Hide records not meeting a condition
 SET FIXED       Toggle fixing of the number of decimal digits displayed
 SET FORMAT*     Activate a format when READ is executed
 SET FUNCTION    Assign a character string to a function key
 SET INDEX       Open one or more order bags in the current work area
 SET INTENSITY   Toggle enhanced display of GETs and PROMPTs
 SET KEY         Assign a procedure invocation to a key
 SET MARGIN      Set the page offset for all printed output
 SET MEMOBLOCK   Change the block size for memo files
 SET MESSAGE     Set the @...PROMPT message line row
 SET OPTIMIZE    Change the setting that optimizes using open orders
 SET ORDER       Select the controlling order
 SET PATH        Specify the CA-Clipper search path for opening files
 SET PRINTER     Toggle echo of output to printer or set the print destination
 SET PROCEDURE*  Compile procedures and functions into the current object file
 SET RELATION    Relate two work areas by a key value or record number
 SET SCOPE       Change the boundaries for scoping keys in controlling order
 SET SCOPEBOTTOM Change bottom boundary for scoping keys in controlling order
 SET SCOPETOP    Change top boundary for scoping keys in controlling order
 SET SCOREBOARD  Toggle the message display from READ or MEMOEDIT()
 SET SOFTSEEK    Toggle relative seeking
 SET TYPEAHEAD   Set the size of the keyboard buffer
 SET UNIQUE*     Toggle inclusion of non-unique keys into an index
 SET WRAP*       Toggle wrapping of the highlight in menus
 SKIP            Move the record pointer to a new position
 SORT            Copy to a database (.dbf) file in sorted order
 STORE*          Assign a value to one or more variables
 SUM             Sum numeric expressions and assign results to variables
 TEXT*           Display a literal block of text
 TOTAL           Summarize records by key value to a database (.dbf) file
 TYPE            Display the contents of a text file
 UNLOCK          Release file/record locks set by the current user
 UPDATE          Update current database file from another database file
 USE             Open an existing database (.dbf) and its associated files
 WAIT*           Suspend program processing until a key is pressed
 ZAP             Remove all records from the current database file

 

Clipper and Networking

Clipper and Networking