関連ワード:  explain ddl statement in sql    explain ddl commands in sql    explain ddl commands in sql with example    explain ddl command in sql with syntax and example    define ddl commands in sql    explain all ddl commands in sql server with example    explain ddl and dml statements in sql    explain ddl and dml commands in sql    explain ddl and dml commands in sql with syntax    explain any two ddl commands in sql with example