Estimating number of iterations or self joins required to evaluate iterative or recursive database queries

A device that includes one or more processors configured to:

• estimate a projected number of iterations required to execute a database query that requires multiple sub-queries to be executed as multiple iterations such that a result of a first one of the sub-queries is needed to be determined in a first iteration of the iterations in order to determine a result of a second one of the sub-quires in a second iteration of the iterations to be performed after the first iteration;
• and
• determine at least one execution plan for executing one or more of the iterations, at least partly based on the projected number of iterations required to execute the database query.

A non-transitory computer readable storage medium storing at least executable code for facilitating execution of a database query of a database, wherein the database query requires multiple sub-queries to be executed as multiple iterations such that a result of a first one of the sub-queries is needed to be determined in a first iteration of the iterations in order to determine a result of a second one of the sub-quires in a second iteration of the iterations to be performed after the first iteration, and wherein the executable code includes:

• executable code for estimating a projected number of iterations required to execute the database query including the first and second iterations;
• and
• executable code for determining at least one execution plan for executing one or more of the iterations, at least partly based on the projected number of iterations required to execute the database query.