I need to identify columns with missing values and calculate the percentage of missing data for each. Let me start by checking what tables exist and their structure. ```json { "action": "tool_call", "reasoning": "I need to profile all columns across all tables to find which ones have missing values. The card shows 10 raw tables. I'll write a single SQL query that aggregates null counts and percentages across all columns in all tables, using the analytics.column_overview metadata which contains null_count for each column.", "tool": "query_sql", "args": { "sql": "SELECT table_name, column_name, null_count, (null_count * 100.0 / (SELECT row_count FROM analytics.table_overview t WHERE t.table_name = c.table_name)) AS missing_percentage FROM analytics.column_overview c WHERE null_count > 0 ORDER BY missing_percentage DESC, table_name, column_name", "purpose": "Find all columns with missing values and calculate the percentage missing in each", "source": "raw" } } ```