Adaptive Server Enterprise ODBC Driver Support

To enable LOB locator support, establish a connection to Adaptive Server with the EnableLOBLocator connection property set to 1.

When EnableLOBLocator is set to 0, the default value, the ODBC Driver cannot retrieve a locator for a LOB column. When enabling LOB Locators, the connection should be set to autocommit off.

You must also include the sybasesqltypes.h file in your program. The sybasesqltypes.h file is located in the include directory, under the ODBC installation directory.

• ODBC Datatype Mapping for Locator Support
  The table lists the ODBC datatype mapping for the Adaptive Server locator datatypes.
• Supported Conversions
  The table lists the supported conversions for the Adaptive Server locator datatypes.
• Methods that Support LOB Locators
  ODBC API methods support LOB locators.
• Implicit Conversion of Prefetched LOB Data
  In Adaptive Server Enterprise ODBC Driver 15.7, when Adaptive Server returns a LOB locator, you can use SQLGetData and SQLBindCol to retrieve the underlying prefetched LOB data by binding the column to SQL_C_CHAR or SQL_C_WCHAR for text locators, or to SQL_C_BINARY for image locators.
• Access and Manipulate LOBs Using Locators
  The ODBC API does not directly support LOB locators. An ODBC client application must use Transact-SQL functions to operate on the locators and manipulate LOB values. Adaptive Server Enterprise ODBC Driver introduces several stored procedures to facilitate the use of the required Transact-SQL functions.
• Initializing a Text Locator
  Use sp_drv_create_text_locator to create a text_locator and optionally initialize it with a value. sp_drv_create_text_locator accesses the Transact-SQL function create_locator.
• Initializing a Unitext Locator
  Use sp_drv_create_unitext_locator to create a unitext_locator and optionally initialize it with value. sp_drv_create_unitext_locator accesses the Transact-SQL function create_locator.
• Initializing an Image Locator
  Use sp_drv_create_image_locator to create an image_locator and optionally initialize it with value. sp_drv_create_image_locator accesses the Transact-SQL function create_locator.
• Obtaining Complete Text Value from a Text Locator
  Use sp_drv_locator_to_text, which accesses the Transact-SQL function return_lob
• Obtaining Complete Unitext Value from a Unitext Locator
  Use sp_drv_locator_to_unitext, which accesses the Transact-SQL function return_lob
• Obtaining Complete Image Value from an Image Locator
  Use sp_drv_locator_to_image, which accesses the Transact-SQL function return_lob.
• Obtaining a Substring from a Text Locator
  Use sp_drv_text_substring, which accesses the Transact-SQL function substring.
• Obtaining a Substring from a Unitext Locator
  Use sp_drv_unitext_substring, which accesses the Transact-SQL function substring.
• Obtaining a Substring from an Image Locator
  Use sp_drv_image_substring, which accesses the Transact-SQL function substring.
• Inserting Text at Specified Position
  Use sp_drv_text_setdata, which accesses the Transact-SQL function setadata.
• Inserting Unitext at Specified Position
  Use sp_drv_unitext_setdata, which accesses the Transact-SQL function setadata.
• Inserting an Image at Specified Position
  Use sp_drv_image_setdata, which accesses the Transact-SQL function setadata.
• Inserting Text Referenced by a Locator
  Use sp_drv_text_locator_setdata, which accesses the Transact-SQL function setadata.
• Inserting Unitext Referenced by a Locator
  Use sp_drv_unitext_locator_setdata, which accesses the Transact-SQL function setadata.
• Inserting Image Referenced by a Locator
  Use sp_drv_image_locator_setdata, which accesses the Transact-SQL function setadata.
• Truncating Underlying LOB Data
  Use truncate lob to truncate the LOB data referenced by a LOB locator.
• Finding Character Length of Underlying Text Data
  Use sp_drv_text_locator_charlength to find the character length of a LOB column referenced by a text locator. sp_drv_text_locator_charlength accesses the Transact-SQL function char_length.
• Finding Byte Length of Underlying Text Data
  Use sp_drv_text_locator_bytelength to find the byte length of a LOB column referenced by a text locator. sp_drv_text_locator_bytelength accesses the Transact-SQL function data_length.
• Finding Character Length of Underlying Unitext Data
  Use sp_drv_unitext_locator_charlength to find the character length of a LOB column referenced by a unitext locator. sp_drv_unitext_locator_charlength accesses the Transact-SQL function char_length.
• Finding Byte Length of Underlying Unitext Data
  Use sp_drv_unitext_locator_bytelength to find the byte length of a LOB column referenced by a unitext locator. sp_drv_unitext_locator_bytelength accesses the Transact-SQL function data_length.
• Finding Byte Length of Underlying Image Data
  Use sp_drv_image_locator_bytelength to find the byte length of a LOB column referenced by an image locator. sp_drv_image_locator_bytelength accesses the Transact-SQL function data_length.
• Finding Position of a Search String within the Text Column Referenced by a Locator
  Use sp_drv_varchar_charindex, which accesses the Transact-SQL function charindex.
• Finding Position of a String Referenced by a Text Locator within the Text Column Referenced by Another Locator
  Use sp_drv_textlocator_charindex, which accesses the Transact-SQL function charindex.
• Finding Position of a Search String within the Unitext Column Referenced by a Locator
  Use sp_drv_univarchar_charindex, which accesses the Transact-SQL function charindex.
• Finding Position of a String Referenced by a Unitext Locator within the Unitext Column Referenced by Another Locator
  Use sp_drv_unitext_locator_charindex, which accesses the Transact-SQL function charindex.
• Finding Position of a Byte Sequence within the Column Referenced by an Image Locator
  Use sp_drv_varbinary_charindex, which accesses the Transact-SQL function charindex.
• Finding Position of Byte Sequence Referenced by an Image Locator within the Image Column Referenced by Another Locator
  Use sp_drv_image_locator_charindex, which accesses the Transact-SQL function charindex.
• Checking if a text_locator Reference is Valid
  Use sp_drv_text_locator_valid, which accesses locator_valid.
• Checking if a unitext_locator Reference is Valid
  Use sp_drv_unitext_locator_valid, which accesses locator_valid.
• Checking if an image_locator Reference is Valid
  Use sp_drv_image_locator_valid, which accesses locator_valid.
• LOB Locator Deallocation
  Use deallocate locator to freeing or deallocating a LOB Locator.
• LOB Locator Examples
  There are six LOB locator examples available.