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Apr 19, 2023 · Databases

How MySQL Expands the '*' in SELECT Statements: Source Code Analysis

This article explains how MySQL 8.0.32 expands the '*' in a SELECT statement into all table columns, detailing the lexical parsing, query preparation, and the functions Item_asterisk::itemize, Query_block::prepare, Query_block::setup_wild, and insert_fields through source‑code excerpts.