A method for partitioning an association table in a distributed database, where a manager determines a first data table in data tables requiring partition and generates a colocation partition (CP) table set of the first data table, the CP table set of the first data table includes the first data table and at least one CP table of the first data table, and a CP table of the first data table includes a data table whose partition key includes a subset of a partition key of the first data table. The manager partitions the first data table according to the partition key and partitions each CP table in the CP table set, a partition range of a partition key of each CP table is the same as a partition range of a corresponding partition key in the first data table.