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integration:rawdata:fixed:limitations [2011/03/14 14:21]
127.0.0.1 external edit
integration:rawdata:fixed:limitations [2016/06/28 22:38] (current)
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   * **Datatypes** - Fixed-length files can store nearly every datatype supported by Omnidex, including proprietary datatypes such as ORACLE DATETIME or ODBC DATETIME.  An exception to this is the relational datatypes, VARCHAR and CLOB.  These datatypes cannot be represented in fixed-length files because they require separate storage for length and NULL indicators.  For fixed-length files, the STRING and CHARACTER datatypes should be used instead.   * **Datatypes** - Fixed-length files can store nearly every datatype supported by Omnidex, including proprietary datatypes such as ORACLE DATETIME or ODBC DATETIME.  An exception to this is the relational datatypes, VARCHAR and CLOB.  These datatypes cannot be represented in fixed-length files because they require separate storage for length and NULL indicators.  For fixed-length files, the STRING and CHARACTER datatypes should be used instead.
  
-  * **NULL's** - Fixed-length files are not capable of differentiating a NULL column as is done in relational databases. Omnidex will treats empty fields as NULL fields to compensate for this. For character-class datatypes, an IS NULL test will qualify any row containing an empty space in that column. For binary-class datatypes, an IS NULL test will qualify any row containing a zero in that column.+  * **NULL's** - Fixed-length files are not capable of differentiating a NULL column as is done in relational databases. Omnidex will treat empty fields as NULL fields to compensate for this. For character-class datatypes, an IS NULL test will qualify any row containing an empty space in that column. For binary-class datatypes, an IS NULL test will qualify any row containing a zero in that column.
  
   * **Deletes** - Omnidex supports INSERT and UPDATE statements against fixed-length files, but it cannot support the DELETE statement.  If DELETE statements are required, consider using [[admin:features:ost:home|Omnidex Standalone Tables]].   * **Deletes** - Omnidex supports INSERT and UPDATE statements against fixed-length files, but it cannot support the DELETE statement.  If DELETE statements are required, consider using [[admin:features:ost:home|Omnidex Standalone Tables]].
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   * **Security** - Fixed-length data files are not encrypted as they might be in a relational database.  Care should be taken with file system security to properly protect the data.   * **Security** - Fixed-length data files are not encrypted as they might be in a relational database.  Care should be taken with file system security to properly protect the data.
  
-Despite these limitations, fixed-length files usually provide the most flexible, portable and high-performing solution possible, and are a favorite solution with Omnidex.+Despite these limitations, fixed-length files usually provide the most flexible, portableand high-performing solution possible, and are a favorite solution with Omnidex.
  
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