| 摘要 |
In an embodiment, a recursive query is received that comprises a first select statement with a seed select statement and a second select statement with a recursive reference, wherein the recursive query further identifies at least two columns in at least one table, wherein the at least two columns have parent-child relationships represented by nodes in a graph, wherein the graph represents the organization of values in rows in the at least one table. A target recursion depth is calculated for the graph based on a fanout of the graph. In an embodiment, the target recursion depth is calculated by summing the fanout at each recursion depth of the graph multiplied by a number of nodes at each recursion depth of the graph. An estimated number of rows that the recursive query will return is estimated based on the target recursion depth. |
