It is an object of this invention to realize high-speed database
retrieval. More specifically, it is an object of this invention to
increase a retrieval speed when data corresponding to an input character
string are retrieved from a database having a trie structure. In order to
achieve the above object, a database retrieval apparatus according to the
invention can retrieve data corresponding to an input character string
from a database having a trie structure, and includes a plurality of
child node search units for searching for a child node corresponding to
the input character string at each node of the trie structure, and a
setting unit for setting, in advance for each node, one of the plurality
of child node search unit which is to be used at each node. Data held in
the database is retrieved by searching for a child node using the child
node search unit set for each node by the setting unit.