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SQL Engine - SQL processing (Sql Compiler) in Calcite

The query planning process is the entire process that takes a SQL to a result.

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Process

The process can be resumed as follow:

• Phase 1: The Sql statement (Query) is parsed to build a parse tree (SqlNode) via the SqlParser
• Phase 2: The Sql tree is validated against the metadata (table exist ?,…)
• Phase 3: Converts the SQL tree (SqlNode) into a logical plan (RelNode)
• Phase 4: Optimize. The ogical plan is rewritten into a physical plan by the optimizer.
• Phase 5: Executions - Run the optimized relational expression (ie the physical plan)

Planner

Calcite has a tool called the planner to perform this process.

Example

See Calcite - Getting Started (from Sql to Resultset)