BuildInternalIndex()
Summary
Builds a permanent index on a field in a table.
Syntax
BuildInternalIndex(string field_spec)
| Argument | Contents |
|---|---|
| field_spec | The field spec of the field to be indexed |
Notes
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An internal index is used for sorting and searching in the indexed field.
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Works on dBASE, fixed-format text, fixed-format binary, and comma-separated text tables.
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If an index file for this table already exists, it is modified. Otherwise a new index file is created.
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Index files have these extensions:
| File Type | Extension |
|---|---|
| dBASE | MDX (default) or .CDX (FoxPro-styled) |
| fixed-format text | AX |
| fixed-format binary | BX |
| comma-separated text | CSX |
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BuildInternalIndex() fails if the program cannot obtain exclusive read-write permissions to the data and index files. This happens, for example, when the file is read-only, or opened by another user or application.
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An internal index cannot contain an expression field.
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If an internal index for this field already exists, BuildInternalIndex() signals an error.
Example
BuildInternalIndex("[U.S. States].Population")
BuildInternalIndex("Employee.LNAME")Error Codes
| Error Type | Meaning |
|---|---|
| Error | The program cannot create a new index file or cannot obtain exclusive read-write permissions to the index and data files;or the underlying index file structure does not support such an index (e.g., dBASE cannot index a logical field); or the specified index exists already; or there are file I/O errors (e.g., out of disk space). |
| NotFound | The specified field does not exist |