Task for the laboratory work
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Теги реферата: культурология шпаргалки, реферат цена
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[[TYPE] DIF | MOD | SYLK | WK1 | WKS | WR1 | WRK | XLS]]
Remarks
Use EXPORT to use FoxPro data in other software packages.
If the table/.DBF you are exporting from is indexed, the new file created is created in the indexed order.
Clauses
Include the name of the file to which FoxPro exports data. If you do not include an extension with the file name, the default extension for the specified file type is assigned.
FIELDS
Include FIELDS to specify which fields are copied to the new file. If the FIELDS clause is omitted, all fields are copied to the new file. Memo and general fields are not copied to the new file even if their names are included in the field list.
The scope clauses are: ALL, NEXT , RECORD , and REST. These are explained in the Overview of the FoxPro Language chapter in the FoxPro Language Reference. Commands which include operate only on the table/.DBF in the active work area.
You can specify a scope of records to copy to the new file. Only the records that fall within the range of records specified by the scope are copied to the new file.
The default scope for EXPORT is ALL records.
FOR
If the FOR clause is included, only records that satisfy the logical condition are copied to the new file. Including the FOR clause lets you conditionally copy records, filtering out undesired records.
Rushmore optimizes an EXPORT ... FOR command if is an optimizable expression. For best performance, use an optimizable expression in the FOR clause. A discussion of Rushmore optimizable expressions appears in the Optimizing Your Application chapter in the FoxPro Developer's Guide.
WHILE
If the WHILE clause is included, records are copied to the new file for as long as the logical expression evaluates to true (.T.).
NOOPTIMIZE
To cause Rushmore not to optimize EXPORT, include NOOPTIMIZE. For more information, see SET OPTIMIZE and the Rushmore discussion in the Optimizing Your Application chapter of the FoxPro Developer's Guide
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TYPE
You must specify the type of file to be created. The TYPE key word is optional, but you must specify one of the following file types.
DIF
When you specify DIF, each field from a FoxPro table/.DBF becomes a vector (column) and each record becomes a tuple (row) in a DIF (Data Interchange Format) file, used by VisiCalc. The new file name is assigned a .DIF extension if an extension isn't included in .
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