Large-scale table data stored in a shared memory are sorted by a plurality of processors in parallel. The mold material for metal casting contains hemihydrate gypsum and a heat resistant material, wherein an oxoacid salt of phosphorus, insoluble in water, is contained in the mold material. in melting point and in the range of 5 to 15 mass % in ratio for which unsaturated dicarboxylic acid -derived structural units account in its structure. The flexible pipe joint effectively suppresses impediments to the flow volume such as the deposition of sludge and grime while ensuring the intended bendability due to relative sliding of a partially spherical outer circumferential surface of a first pipe member and a partially spherical inner circumferential surface of a second pipe member.