The Schema Mismatch Problem with BigQuery Wildcard Tables
What are wildcard tables? Wildcard tables provide a concise way to query multiple tables that share a common naming pattern and schema. A wildcard table effectively represents a UNION of all tables matching a specified wildcard expression (e.g., table_prefix*). When you query a wildcard table, BigQuery treats the matching tables as a single logical table. A special pseudo-column, _TABLE_SUFFIX, is automatically included in the query results. This column contains the value matched by the wildcard character for each row, allowing you to identify the source table. ...