Plan Parser

The Plan Parser is a core component within the Query Plan Interpreter system. Its primary role is to receive, decode, and structurally analyze execution plans generated by database query optimizers. It breaks down the plan's hierarchical tree or graph structure, identifying individual operations (nodes), their execution order, dependencies, and associated metadata to prepare the data for subsequent visualization, cost analysis, or optimization feedback.

The parser operates by sequentially reading the input query plan data, which is typically in a structured format like XML, JSON, or a proprietary binary. It applies syntactic and semantic rules to validate the plan's structure, then constructs an internal object model (e.g., an abstract syntax tree or graph) representing the plan's operators (scans, joins, sorts, aggregates) and their properties (estimated rows, cost, predicates). This model serves as the foundation for all downstream interpretation tasks.