By using CAST operator, you can execute an explicit type change between BLOB/CLOB type and binary type/string type. For more details, see CAST Operator.
CAST (<bit_type_column_or_value> AS CLOB)
CAST (<bit_type_column_or_value> AS BLOB)
CAST (<char_type_column_or_value> AS BLOB)
CAST (<char_type_column_or_value> AS CLOB)
The next table shows the functions provided to process and change BLOB/CLOB types.
Function Expression |
Description |
---|---|
CLOB_TO_CHAR (<clob_type_column>) |
Changes number type, date/time type, and CLOB type to VARCHAR type. |
BLOB_TO_BIT (<blob_type_column>) |
Changes BLOB type to VARYING BIT type. |
CHAR_TO_CLOB(<char_type_column_or_value>) |
Changes text string type (CHAR, VARCHAR, NCHAR, NVACHAR) to CLOB type. |
BIT_TO_BLOB(<blob_type_column_or_value>) |
Changes bit array type (BIT, VARYING BIT) to BLOB type. |
CHAR_TO_BLOB(<char_type_colulmn_or_value>) |
Changes text string type (CHAR, VARCHAR, NCHAR, NVACHAR) to BLOB type. |
CLOB_FROM_FILE(<file_pathname>) |
Reads file details from the file path of VARCHAR type and changes to CLOB type data. <file_pathname> is analyzed to a path of server which is operated by the DB client, such as CAS or CSQL. If a path is specified targeting this, the upper path will be the current work direction of the process. |
BLOB_FROM_FILE(<file_pathname>) |
Reads file details from the file path of VARCHAR type, and changes to BLOB type data. The file path specified in is interpreted using the same method as the CLOB_FROM_FILE( ) function. |
CLOB_LENGTH(<clob_column>) |
Returns the length of LOB data stored in a CLOB file in bytes. |
BLOB_LENGTH(<blob_column>) |
Returns the length of LOB data stored in a BLOB file in bytes. |
<blob_or_clob_column> IS NULL |
Use an IS NULL expression to compare whether it is a LOB column value (Locator) or NULL; returns TRUE if NULL. |