I need to identify columns with missing values and calculate the percentage of missing data for each column in the Olympic Table Tennis dataset. Let me query the column metadata to get null counts for all columns: ```json { "action": "tool_call", "reasoning": "I'll query the analytics.column_overview metadata table to get null counts for all columns in the dataset. This will show me which columns have missing values and allow me to calculate the percentage missing.", "tool": "query_sql", "args": { "sql": "SELECT table_name, column_name, null_count, (SELECT row_count FROM analytics.table_overview WHERE table_name = co.table_name) as total_rows, ROUND(100.0 * null_count / (SELECT row_count FROM analytics.table_overview WHERE table_name = co.table_name), 2) as pct_missing FROM analytics.column_overview co WHERE table_name = 'raw.olympic_table_tennis_medals_1988_2024' ORDER BY null_count DESC", "purpose": "Get null counts and percentages for all columns to identify which have missing values", "source": "raw" } } ```