在虚拟机上测评了下MySQL 和 PostgreSQL 的各种LOAD FILE方式以及时间。 因为是虚拟机上的测评,所以时间只做参考,不要太较真, 看看就好了。

MySQL 工具:

   1. 自带mysqlimport工具。

   2. 命令行 load data infile ...

   3. 利用mysql-connector-python Driver来写的脚本。

PostgreSQL 工具:

   1. pgloader 第三方工具。

   2. 命令行 copy ... from ...

   3. 利用psycopg2写的python 脚本。

测试表结构:

mysql> desc t1;
+----------+-----------+------+-----+-------------------+-------+
| Field    | Type      | Null | Key | Default           | Extra |
+----------+-----------+------+-----+-------------------+-------+
| id       | int(11)   | NO   | PRI | NULL              |       |
| rank     | int(11)   | NO   |     | NULL              |       |
| log_time | timestamp | YES  |     | CURRENT_TIMESTAMP |       |
+----------+-----------+------+-----+-------------------+-------+
3 rows in set (0.00 sec)
mysql> select count(*) from t1;
+----------+
| count(*) |
+----------+
|  1000000 |
+----------+
1 row in set (6.80 sec)

测试CSV文件:

t1.csv


MySQL 自身的loader: (时间24妙)


mysql> load data infile '/tmp/t1.csv' into table t1 fields terminated by ',' enclosed by '"' lines terminated by '\r\n';
Query OK, 1000000 rows affected (24.21 sec)
Records: 1000000  Deleted: 0  Skipped: 0  Warnings: 0

MySQL python 脚本:(时间23秒)

>>>

Running 23.289 Seconds


MySQL 自带mysqlimport:(时间23秒)

[root@mysql56-master ~]# time mysqlimport t_girl '/tmp/t1.csv' --fields-terminated-by=',' --fields-enclosed-by='"' --lines-terminated-by='\r\n' --use-threads=2 -uroot -proot
t_girl.t1: Records: 1000000  Deleted: 0  Skipped: 0  Warnings: 0
real    0m23.664s
user    0m0.016s
sys     0m0.037s


PostgreSQL 自身COPY:(时间7秒)

t_girl=# copy t1 from '/tmp/t1.csv' with delimiter ',';
COPY 1000000
Time: 7700.332 ms

Psycopg2 驱动copy_to方法:(时间6秒)

[root@postgresql-instance scripts]# python load_data.py
Running 5.969 Seconds.


Pgloader 导入CSV:(时间33秒)

[root@postgresql-instance ytt]# pgloader commands.load     
                    table name       read   imported     errors            time
                        ytt.t1    1000000    1000000          0         33.514s
------------------------------  ---------  ---------  ---------  --------------
------------------------------  ---------  ---------  ---------  --------------
             Total import time    1000000    1000000          0         33.514s
Pgloader 直接从MySQL 拉数据:(时间51秒)
[root@postgresql-instance ytt]# pgloader commands.mysql
                    table name       read   imported     errors            time
               fetch meta data          2          2          0          0.138s
------------------------------  ---------  ---------  ---------  --------------
                            t1    1000000    1000000          0         51.136s
------------------------------  ---------  ---------  ---------  --------------
------------------------------  ---------  ---------  ---------  --------------
------------------------------  ---------  ---------  ---------  --------------
             Total import time    1000000    1000000          0         51.274s


附上commands.load和commands.mysql

commands.load:
LOAD CSV 
   FROM '/tmp/ytt.csv' WITH ENCODING UTF-8
        ( 
           id, rank, log_time 
        ) 
   INTO postgresql://t_girl:[email protected]:5432/t_girl?ytt.t1
   WITH skip header = 0, 
        fields optionally enclosed by '"', 
        fields escaped by backslash-quote, 
        fields terminated by ',' 
    SET work_mem to '32 MB', maintenance_work_mem to '64 MB';
commands.mysql:
LOAD DATABASE 
     FROM mysql://python_user:[email protected]:3306/t_girl?t1
     INTO postgresql://t_girl:[email protected]:5432/t_girl?ytt.t1
 with data only
  SET maintenance_work_mem to '64MB', 
      work_mem to '3MB', 
      search_path to 'ytt';

附pgloader 手册:

http://pgloader.io/howto/pgloader.1.html