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本章节通过 TPCH lineitem 表来展现新执行器的应用。
建设 e_lineitem 内部表用来生成 TPCH lineitem 数据,
CREATE EXTERNAL WEB TABLE E_LINEITEM (L_ORDERKEY INT8 ,L_PARTKEY INTEGER ,L_SUPPKEY INTEGER ,L_LINENUMBER INTEGER ,L_QUANTITY FLOAT ,L_EXTENDEDPRICE FLOAT ,L_DISCOUNT FLOAT ,L_TAX FLOAT ,L_RETURNFLAG VARCHAR(1) ,L_LINESTATUS VARCHAR(1) ,L_SHIPDATE TEXT ,L_COMMITDATE TEXT ,L_RECEIPTDATE TEXT ,L_SHIPINSTRUCT CHAR(25) ,L_SHIPMODE VARCHAR(10) ,L_COMMENT VARCHAR(44) )EXECUTE 'bash -c"$GPHOME/bin/dbgen -b $GPHOME/bin/dists.dss -T L -s 1 -N 6 -n $((GP_SEGMENT_ID + 1))"'on 6 format'text'(delimiter'|');创立 ORC 表
CREATE TABLE lineitem(L_ORDERKEY INT8,L_PARTKEY INTEGER,L_SUPPKEY INTEGER,L_LINENUMBER INTEGER,L_QUANTITY FLOAT,L_EXTENDEDPRICE FLOAT,L_DISCOUNT FLOAT,L_TAX FLOAT,L_RETURNFLAG TEXT,L_LINESTATUS TEXT,L_SHIPDATE TEXT,L_COMMITDATE TEXT,L_RECEIPTDATE TEXT,L_SHIPINSTRUCT TEXT,L_SHIPMODE TEXT,L_COMMENT TEXT)WITH (APPENDONLY = true, OIDS = FALSE, ORIENTATION = orc);插入数据
INSERT INTO lineitem SELECT * FROM e_lineitem;
从上面的例子能够看到新执行器对于性能的大幅改良。
----- 获取表行数 ------postgres=# set new_executor = on;SETpostgres=# SELECT COUNT(*) FROM lineitem;count---------6001215(1 row)Time: 17.006 mspostgres=# set new_executor = off;SETpostgres=# SELECT COUNT(*) FROM lineitem;count---------6001215(1 row)Time: 213.248 ms-----TPCH 查问 1 ------postgres=# set new_executor = on;SETpostgres=# SELECTl_returnflag,l_linestatus,sum(l_quantity)::bigint as sum_qty,sum(l_extendedprice)::bigint as sum_base_price,sum(l_extendedprice * (1 - l_discount))::bigint as sum_disc_price,sum(l_extendedprice * (1 - l_discount) * (1 + l_tax))::bigint as sum_charge,avg(l_quantity)::bigint as avg_qty,avg(l_extendedprice)::bigint as avg_price,avg(l_discount)::bigint as avg_disc,count(*) as count_orderFROMlineitemWHEREl_shipdate <= '1998-08-20'GROUP BYl_returnflag,l_linestatus;l_returnflag | l_linestatus | sum_qty | sum_base_price | sum_disc_price | sum_charge | avg_qty | avg_price | avg_disc | count_order--------------+--------------+----------+----------------+----------------+--------------+---------+-----------+----------+-------------R | F | 37719753 | 56568041381 | 53741292685 | 55889619120 | 26 | 38251 | 0 | 1478870N | F | 991417 | 1487504710 | 1413082168 | 1469649223 | 26 | 38284 | 0 | 38854A | F | 37734107 | 56586554401 | 53758257135 | 55909065223 | 26 | 38273 | 0 | 1478493N | O | 73808911 | 110700990251 | 105167436999 | 109377979031 | 26 | 38248 | 0 | 2894278(4 rows)Time: 234.376 mspostgres=# set new_executor = off;SETpostgres=# SELECTl_returnflag,l_linestatus,sum(l_quantity)::bigint as sum_qty,sum(l_extendedprice)::bigint as sum_base_price,sum(l_extendedprice * (1 - l_discount))::bigint as sum_disc_price,sum(l_extendedprice * (1 - l_discount) * (1 + l_tax))::bigint as sum_charge,avg(l_quantity)::bigint as avg_qty,avg(l_extendedprice)::bigint as avg_price,avg(l_discount)::bigint as avg_disc,count(*) as count_orderFROMlineitemWHEREl_shipdate <= '1998-08-20'GROUP BYl_returnflag,l_linestatus;l_returnflag | l_linestatus | sum_qty | sum_base_price | sum_disc_price | sum_charge | avg_qty | avg_price | avg_disc | count_order--------------+--------------+----------+----------------+----------------+--------------+---------+-----------+----------+-------------R | F | 37719753 | 56568041381 | 53741292685 | 55889619120 | 26 | 38251 | 0 | 1478870N | F | 991417 | 1487504710 | 1413082168 | 1469649223 | 26 | 38284 | 0 | 38854A | F | 37734107 | 56586554401 | 53758257135 | 55909065223 | 26 | 38273 | 0 | 1478493N | O | 73808911 | 110700990251 | 105167436999 | 109377979031 | 26 | 38248 | 0 | 2894278(4 rows)Time: 2341.147 ms正文完