code: public SQLUnit generateSQL(final TableUnit tableUnit, final SQLBuilder sqlBuilder, final ShardingDataSourceMetaData shardingDataSourceMetaData) {
          return sqlBuilder.toSQL(tableUnit, getTableTokens(tableUnit), shardingRule, shardingDataSourceMetaData);
      }
docs: Generate SQL string.
  
  @param tableUnit route table unit
  @param sqlBuilder SQL builder
  @param shardingDataSourceMetaData sharding data source meta data
  @return SQL unit