COPY STRUCTURE EXTENDED
Copy current database structure into a definition file
Syntax
COPY STRUCTURE EXTENDED TO <xcFileName>
Arguments
<xcFileName> The name of the target definition file to create. (.dbf) is the default extension if none is given. It can be specified as a literal file name or as a character expression enclosed in parentheses.
Description
COPY STRUCTURE EXTENDED create a new database named <cFileName> with a pre-defined structure (also called “structure extended file” ) :
Field name Type Length Decimals
----------- ---- ------ ---------
FIELD_NAME C 10 0
FIELD_TYPE C 1 0
FIELD_LEN N 3 0
FIELD_DEC N 3 0
Each record in the new file contains information about one field in the original file. CREATE FROM could be used to create a database from the structure extended file.
For prehistoric compatibility reasons, Character fields which are longer than 255 characters are treated in a special way by writing part of the length in the FIELD_DEC according to the following formula (this is done internally) :
FIELD->FIELD_DEC := int( nLength / 256 )
FIELD->FIELD_LEN := ( nLength % 256 )
Later if you want to calculate the length of a field you can use the following formula:
nLength := iif( FIELD->FIELD_TYPE == "C", ;
FIELD->FIELD_DEC * 256 + FIELD->FIELD_LEN, ;
FIELD->FIELD_LEN )
COPY STRUCTURE EXTENDED command is preprocessed into __dbCopyXStruct() function during compile time.
Examples
// Open a database, then copy its structure to a new file,
// Open the new file and list all its records
USE Test
COPY STRUCTURE EXTENDED TO TestStru
USE TestStru
LIST
Compliance
Clipper
Platforms
All
Seealso
COPY STRUCTURE, CREATE, CREATE FROM, DBCREATE(), DBSTRUCT(), __dbCopyStruct(), __dbCopyXStruct(), __dbCreate()