USE specifies a graph space as the current working graph space for subsequent queries.
USE statement requires some privileges for the graph space. Otherwise, Nebula Graph throws an error.
# The following example specifies space1 as the current working graph space.
nebula> USE space1;
# The following example traverses in space1.
nebula> GO FROM 1 OVER edge1;
# The following example specifies space2 as the current working graph space.
nebula> USE space2;
# The following example traverses in space2. Hereafter, you cannot read any data from space1, because these vertices and edges being traversed have no relevance with space1.
nebula> GO FROM 2 OVER edge2;
You cannot use two graph spaces in one statement.
Different from Fabric Cypher, graph spaces in Nebula Graph are fully isolated from each other. Making a graph space as the working graph space prevents you from accessing other spaces. The only way to traverse in a new graph space is to switch by the
USE statement. In Fabric Cypher, you can use two graph spaces in one statement (using the
USE + CALL syntax). But in Nebula Graph, you can only use one graph space in one statement.