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SQL Correctness Rubric

When evaluating SQL in agent traces, check these dimensions:

1. Unity Catalog Namespace

• Must use 3-level namespace: catalog.schema.table
• Never use unqualified table names
• Catalog/schema should match the user's context (not hardcoded main.default unless appropriate)

2. Modern DDL Syntax

• Use CREATE OR REPLACE instead of DROP IF EXISTS + CREATE
• Use ALTER TABLE ... SET TBLPROPERTIES for table properties
• Use COMMENT ON for documentation

3. Tool Selection

• Must use mcp__databricks__execute_sql for SQL execution
• Must NOT use Bash with databricks sql CLI as a workaround
• Must NOT use notebook execution for simple queries

4. Databricks SQL Features

• Use Delta-specific syntax where appropriate (MERGE INTO, OPTIMIZE, VACUUM)
• Use IDENTIFIER() function for dynamic table references
• Use SELECT * FROM read_files() for file ingestion, not COPY INTO (unless streaming)

5. Syntax Validity

• SQL must be syntactically valid for Databricks SQL (Spark SQL dialect)
• String literals use single quotes, identifiers use backticks if needed
• Semicolons at statement boundaries

6. Safety

• No string interpolation for user-provided values in SQL
• Use parameterized queries where applicable
• No DROP operations unless explicitly requested

See detailed patterns for specific syntax examples.