# 验证并行查询效果
本章节使用TPCH测试工具测试并行查询对22条QUERY的性能提升情况。
测试的实例信息如下：
- 实例规格：32 vCPUs \| 256 GB
- 内核版本：2.0.26.1
- 并行线程数：16
- 测试数据量：100GB
#### 操作步骤
1. 生成测试数据。 
   1. 请[下载TPCH源码](https://github.com/electrum/tpch-dbgen)。
   
   2. 请在下载的源码文件中，找到makefile.suite文件，并按照如下内容进行修改，修改完成后进行保存。
      ```
      CC      = gcc
      # Current values for DATABASE are: INFORMIX, DB2, TDAT (Teradata)
      #                                  SQLSERVER, SYBASE, ORACLE
      # Current values for MACHINE are:  ATT, DOS, HP, IBM, ICL, MVS,
      #                                  SGI, SUN, U2200, VMS, LINUX, WIN32
      # Current values for WORKLOAD are:  TPCH
      DATABASE= SQLSERVER
      MACHINE = LINUX
      WORKLOAD = TPCH
      ```
      
   
   3. 在源码根目录下，执行下列命令，编译生成TPCH数据工具dbgen。
      ```
      make -f makefile.suite
      ```
      
   
   4. 使用dbgen执行如下命令，生成TPCH数据100GB。
      ```
      ./dbgen -s 100
      ```
      
   
   
   
   
2. 登录目标TaurusDB实例，创建目标数据库，并使用如下命令创建TPCH的表。 
   ```
   CREATE TABLE nation  ( N_NATIONKEY  INTEGER NOT NULL,
                          N_NAME       CHAR(25) NOT NULL,
                          N_REGIONKEY  INTEGER NOT NULL,
                          N_COMMENT    VARCHAR(152));
   CREATE TABLE region  ( R_REGIONKEY  INTEGER NOT NULL,
                          R_NAME       CHAR(25) NOT NULL,
                          R_COMMENT    VARCHAR(152));
   CREATE TABLE part    ( P_PARTKEY     INTEGER NOT NULL,
                          P_NAME        VARCHAR(55) NOT NULL,
                          P_MFGR        CHAR(25) NOT NULL,
                          P_BRAND       CHAR(10) NOT NULL,
                          P_TYPE        VARCHAR(25) NOT NULL,
                          P_SIZE        INTEGER NOT NULL,
                          P_CONTAINER   CHAR(10) NOT NULL,
                          P_RETAILPRICE DECIMAL(15,2) NOT NULL,
                          P_COMMENT     VARCHAR(23) NOT NULL );
   CREATE TABLE supplier  ( S_SUPPKEY     INTEGER NOT NULL,
                            S_NAME        CHAR(25) NOT NULL,
                            S_ADDRESS     VARCHAR(40) NOT NULL,
                            S_NATIONKEY   INTEGER NOT NULL,
                            S_PHONE       CHAR(15) NOT NULL,
                            S_ACCTBAL     DECIMAL(15,2) NOT NULL,
                            S_COMMENT     VARCHAR(101) NOT NULL);
   CREATE TABLE partsupp  ( PS_PARTKEY     INTEGER NOT NULL,
                            PS_SUPPKEY     INTEGER NOT NULL,
                            PS_AVAILQTY    INTEGER NOT NULL,
                            PS_SUPPLYCOST  DECIMAL(15,2)  NOT NULL,
                            PS_COMMENT     VARCHAR(199) NOT NULL );
   CREATE TABLE customer  ( C_CUSTKEY     INTEGER NOT NULL,
                            C_NAME        VARCHAR(25) NOT NULL,
                            C_ADDRESS     VARCHAR(40) NOT NULL,
                            C_NATIONKEY   INTEGER NOT NULL,
                            C_PHONE       CHAR(15) NOT NULL,
                            C_ACCTBAL     DECIMAL(15,2)   NOT NULL,
                            C_MKTSEGMENT  CHAR(10) NOT NULL,
                            C_COMMENT     VARCHAR(117) NOT NULL);
   CREATE TABLE orders  ( O_ORDERKEY       INTEGER NOT NULL,
                          O_CUSTKEY        INTEGER NOT NULL,
                          O_ORDERSTATUS    CHAR(1) NOT NULL,
                          O_TOTALPRICE     DECIMAL(15,2) NOT NULL,
                          O_ORDERDATE      DATE NOT NULL,
                          O_ORDERPRIORITY  CHAR(15) NOT NULL,
                          O_CLERK          CHAR(15) NOT NULL,
                          O_SHIPPRIORITY   INTEGER NOT NULL,
                          O_COMMENT        VARCHAR(79) NOT NULL);
   CREATE TABLE lineitem ( L_ORDERKEY    INTEGER NOT NULL,
                           L_PARTKEY     INTEGER NOT NULL,
                           L_SUPPKEY     INTEGER NOT NULL,
                           L_LINENUMBER  INTEGER NOT NULL,
                           L_QUANTITY    DECIMAL(15,2) NOT NULL,
                           L_EXTENDEDPRICE  DECIMAL(15,2) NOT NULL,
                           L_DISCOUNT    DECIMAL(15,2) NOT NULL,
                           L_TAX         DECIMAL(15,2) NOT NULL,
                           L_RETURNFLAG  CHAR(1) NOT NULL,
                           L_LINESTATUS  CHAR(1) NOT NULL,
                           L_SHIPDATE    DATE NOT NULL,
                           L_COMMITDATE  DATE NOT NULL,
                           L_RECEIPTDATE DATE NOT NULL,
                           L_SHIPINSTRUCT CHAR(25) NOT NULL,
                           L_SHIPMODE     CHAR(10) NOT NULL,
                           L_COMMENT      VARCHAR(44) NOT NULL);
   ```
   
   
3. 使用如下命令，将生成的数据导入到TPCH的表中。 
   ```
   load data INFILE '/path/customer.tbl' INTO TABLE customer FIELDS TERMINATED BY '|';
   load data INFILE '/path/region.tbl' INTO TABLE region FIELDS TERMINATED BY '|';
   load data INFILE '/path/nation.tbl' INTO TABLE nation FIELDS TERMINATED BY '|';
   load data INFILE '/path/supplier.tbl' INTO TABLE supplier FIELDS TERMINATED BY '|';
   load data INFILE '/path/part.tbl' INTO TABLE part FIELDS TERMINATED BY '|';
   load data INFILE '/path/partsupp.tbl' INTO TABLE partsupp FIELDS TERMINATED BY '|';
   load data INFILE '/path/orders.tbl' INTO TABLE orders FIELDS TERMINATED BY '|';
   load data INFILE '/path/lineitem.tbl' INTO TABLE lineitem FIELDS TERMINATED BY '|';
   ```
   
   
4. 创建TPCH表的索引。 
   ```
   alter table region add primary key (r_regionkey);
   alter table nation add primary key (n_nationkey);
   alter table part add primary key (p_partkey);
   alter table supplier add primary key (s_suppkey);
   alter table partsupp add primary key (ps_partkey,ps_suppkey);
   alter table customer add primary key (c_custkey);
   alter table lineitem add primary key (l_orderkey,l_linenumber);
   alter table orders add primary key (o_orderkey);
   ```
   
   
5. 请[获取TPCH 22个查询query语句](https://github.com/dragansah/tpch-dbgen/tree/master/tpch-queries)，并进行相应操作。
 
#### 测试结果
通过采用16线程并行查询，其中的17条QUERY的性能得到明显提升，查询速度平均提升10倍以上。TPCH性能测试结果如下图所示。
图1测试结果   
![](https://support.huaweicloud.com/kerneldesc-taurusdb/figure/zh-cn_image_0000001882571656.png "点击放大")