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| == COLUMN column_name == | == COLUMN column_name == | ||
| - | [[[environment_name.]database_name.]table_name.]column_name[(start, length)] | + | [[[environment_name.]database_name.]table_name.]column_name[(start, length)] |
| column_name represents a non-ambiguous column or portion of a column. | column_name represents a non-ambiguous column or portion of a column. | ||
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| DOUBLE Double-precision floating point data stored in 8 bytes. This is equivalent to a “datatype FLOAT length 8”. | DOUBLE Double-precision floating point data stored in 8 bytes. This is equivalent to a “datatype FLOAT length 8”. | ||
| + | |||
| <code> | <code> | ||
| Figure 2 - Examples of Declaring Datatypes Using New and Existing Syntax | Figure 2 - Examples of Declaring Datatypes Using New and Existing Syntax | ||
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| OMNIDEX BLOB 1999 bytes bytes + 4 | OMNIDEX BLOB 1999 bytes bytes + 4 | ||
| </code> | </code> | ||
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| ==== LENGTH n ==== | ==== LENGTH n ==== | ||
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| The cardinality of a column is the number of distinct values in the column. This number should be near the actual column cardinality. Omnidex uses this number to better optimize some queries. | The cardinality of a column is the number of distinct values in the column. This number should be near the actual column cardinality. Omnidex uses this number to better optimize some queries. | ||
| + | |||
| + | ===== $RETRIEVE_FILE ===== | ||
| + | |||
| + | <code> | ||
| + | $RETRIEVE_FILE(filename [,’datatype’ [,length [,’options’]]]) | ||
| + | |||
| + | filename A string literal, a column, or an expression containing the filename to retrieve. | ||
| + | |||
| + | datatype The datatype to be used for retrieving the file’s content. Typically a CLOB or C STRING is used to retrieve ASCII data such as text and HTML, and BLOB is used to retrieve binary data such as Microsoft Word and Adobe PDF documents. Alternatively, a CLOB can be used to retrieve the text from Microsoft Word and Adobe PDF documents if the EXTRACT_TEXT option is used. | ||
| + | |||
| + | Datatypes are specified in textual form, and may be used with or without lengths. If no lengths are specified, then they must be included in the length parameter. If no datatype is specified, then CLOB is presumed. | ||
| + | |||
| + | length The length to be used for retrieving the file’s content. Lengths may also be specified in the datatype parameter using the standard Omnidex syntax. If no length is provided in either place, the length defaults to 64KB. | ||
| + | |||
| + | options The options to be applied to retrieving this file. | ||
| + | |||
| + | EXTRACT_TEXT Extract the text from the file, rather than returning the exact contents of the file. | ||
| + | |||
| + | AUTO_EXTENSION If the passed filename does not exist, and if the passed filename does not contain an extension, and if a single file exists with this name plus an extension, the open that file. This option allows filenames to be included without an extension as long as only one file is possible. | ||
| + | STOPWORDS= Use the STOPWORDS list identified by this option. | ||
| + | |||
| + | PARSE Parse the keywords from the text and discard all whitespace and punctuation. | ||
| + | |||
| + | The $RETRIEVE_FILE function returns a buffer using the datatype and length specified in the parameters. If no parameters are specified, then the default datatype and length are returned. | ||
| + | </code> | ||
| + | |||