Method and apparatus for executing query and computer readable medium therefor

An apparatus for executing a query statement in a database management system, the apparatus comprising:

• a database management module in the database management system, where the database management module is configured to cooperate with components in the database management system that include one or more processors to execute instructions, one or more memories to store information, one or more data input components to receive data input from a user of the database management system, a communication circuit to establish a communication link to communicate with other computing devices external to the database management system, a display device to display at least some of the information stored in the one or more memories, where portions of the database management module implemented in software are stored in the one or more memories and are executed by the one or more processors, where the database management module consists of multiple different modules including but not limited to a communication module, a pivot name table query module, a pivot meta table query module, and an output information generating module;
• where the communication module is configured to receive a query statement for requesting BLOB data serialized to a binary large object (BLOB) type and stored in a pivot table;
• where the pivot name table query module is configured to determine name information for one or more columns generated as a result of a pivot operation included in respective pivot columns of the pivot table by querying a pivot name table for the pivot table;
• where the pivot meta table query module is configured to determine internal storage type information of the pivot table by querying a pivot meta table for the pivot table;
• and
• where the output information generating module is configured to generate output information for the BLOB data corresponding to the query statement based on the determined name information and internal storage type information.

A method for executing a query statement in a DBMS, the method comprising:

• receiving the query statement for requesting BLOB data serialized to a binary large object (BLOB) type and stored in a pivot table;
• determining name information for one or more columns generated as a result of a pivot operation included in respective pivot columns of the pivot table by querying a pivot name table for the pivot table;
• determining internal storage type information of the pivot table by querying a pivot meta table for the pivot table;
• and
• generating output information for the BLOB data corresponding to the query statement based on the determined name information and internal storage type information.