code: func (db *mysql) TableCheckSql(tableName string) (string, []interface{}) {
  	args := []interface{}{db.DbName, tableName}
  	sql := "SELECT `TABLE_NAME` from `INFORMATION_SCHEMA`.`TABLES` WHERE `TABLE_SCHEMA`=? and `TABLE_NAME`=?"
  	return sql, args
  }
docs: /*func (db *mysql) ColumnCheckSql(tableName, colName string) (string, []interface{}) {
  	args := []interface{}{db.DbName, tableName, colName}
  	sql := "SELECT `COLUMN_NAME` FROM `INFORMATION_SCHEMA`.`COLUMNS` WHERE `TABLE_SCHEMA` = ? AND `TABLE_NAME` = ? AND `COLUMN_NAME` = ?"
  	return sql, args
  }*/