Index Table Update Method, and Device

A data processing device, comprising:

• a processor;
• and
• a storage coupled to the processor and storing instructions for execution by the processor, wherein the instructions instruct the processor to:
• adjust an index density of a second index table in a memory when storage space occupied by the second index table reaches an upper limit or a lower limit of a preset range, wherein the index density of the second index table is a ratio of a quantity of index records comprised in the second index table to a quantity of index records comprised in a first index table in an external storage, and wherein an index record in the second index table is synchronously updated according to the index density when an index record in the first index table is updated;
• select an index record from the first index table according to the adjusted index density;
• and
• update the second index table using the selected index record.

A computer program product comprising a non-transitory computer-readable medium storing instructions that when executed by a processor instruct the processor to:

• adjust an index density of a second index table in a memory when storage space occupied by the second index table reaches an upper limit or a lower limit of a preset range, wherein the index density of the second index table is a ratio of a quantity of index records comprised in the second index table to a quantity of index records comprised in a first index table in an external storage, and wherein an index record in the second index table is synchronously updated according to the index density when an index record in the first index table is updated;
• select an index record from the first index table according to the adjusted index density;
• and
• update the second index table using the selected index record.