Difference between revisions of "Using Navigational Data Access Commands in Recital"

Revision as of 12:36, 16 December 2009

Using Navigational Data Access Commands in Recital

Why use Navigational Data Access Commands

Creating a Recital Database

• CREATE DATABASE

Opening a Recital Database

• OPEN DATABASE

Creating a Recital Table

• CREATE
• CREATE FROM
• COPY STRUCTURE
• COPY TO
• COPY STRUCTURE EXTENDED
• SQL CREATE TABLE

Opening a Recital Table

• SELECT
• SELECT()
• USE

Navigating a Recital Table

• GOTO
• GOTO()
• INDEX
• REINDEX
• SEEK
• SEEK()
• SKIP

Inserting Records into a Recital Table

• APPEND FROM
• BLANK
• GATHER
• GENERATE
• REPLACE

Updating Records in a Recital Table

• GATHER
• REPLACE

Selecting Records from a Recital Table

• AVERAGE
• COUNT
• DISPLAY
• LIST
• SCAN
• SCATTER
• SUM
• TOTAL

Adding Records to a Recital Table

• APPEND
• APPEND BLANK
• INSERT

Deleting Records in a Recital Table

The deletion of records in a Recital table is a two stage process. The delete command is used to mark a record for deletion. At this stage, the marked record is hidden if set deleted is on. With set deleted set to off, the record is still accessible as normal. Record lists (list and display) will show the deletion marker * next to the record number and the deleted() function will return .T. (true). A record marked for deletion can have the mark removed using the recall command.

• delete

delete [<scope>][for | while <condition as logical>] 

• recall

recall [<scope>][for | while <condition as logical>] 

• set deleted

set deleted on | off 

set deleted off
use example
goto 10
delete
echo deleted() // .T.
recall
echo deleted() // .F.

To physically remove records marked for deletion, the pack command must be issued on the table. The table must be open for exclusive use.

• pack

use example exclusive
pack

The zap command can be used to physically delete all the records from a table immediately. The table must be open for exclusive use.

• zap

use example exclusive
zap

Obtain Information about a Recital Table

• DISPLAY/LIST STRUCTURE
• DISPLAY/LIST INDEX
• DISPLAY/LIST

• BOF()
• EOF()
• FIELD()
• FIELDNAME()
• FLDLIST()
• INUSE()
• RECNO()
• REFERENCES()
• USED()