Abstract: To insert data into a graph database, an insert statement for a target graph database is received, where the insert statement includes at least an insert keyword and several element definition lists corresponding to several graphic elements including nodes and/or edges. The several element definition lists describe respective element identifiers of the several graphic elements and object types of objects represented by the several graphic elements, and each element definition list includes each attribute value of each pre-described attribute of a corresponding graphic element. The insert statement is executed, including forming each data row corresponding to each graphic element based on each attribute value in each element definition list and determining a primary key value of a corresponding data row based on an element identifier and an object type of each graphic element. Each data row is inserted into the target graph database based on the primary key value.

Abstract: The toy car comprises a housing assembly and at least two limiting members, each of the limiting member comprises a first end portion and a second end portion coupled to the first end portion; the first end portion of each limiting member is coupled to the housing assembly, the second end portion of one limiting member is used to contact a side surfaces of the block, and the second end portion of the other limiting member is used to abut against another side surface of the block.

Abstract: A toy car includes a housing assembly and a limiting member. The housing assembly is provided with a plurality of wheels rotatable with respect to the housing assembly. The plurality of wheels is configured for engaging on an upper surface of a block and rolling along the upper surface of the block. The limiting member is connected to the housing assembly. The limiting member is configured for abutting against a side surface of the block, and the limiting member is used for limiting the plurality of wheels on the upper surface of the block.

Abstract: A toy car includes a shell component. The shell component is provided with wheels capable of rotating relative to the shell component. Each of the wheels includes a rolling part and an abutting part. The abutting part is arranged on one side of the rolling part facing away from the shell component. The rolling part is configured to be engaged to an upper surface of a building block and roll along the upper surface of the building block. And the abutting part is configured to abut against a side surface of the building block.