在虚拟机上测评了下MySQL和PostgreSQL的各种LOADFILE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mysqlim
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 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 0m0.037sPostgreSQL 自身COPY:(时间7秒)
t_girl=# copy t1 from '/tmp/t1.csv' with delimiter ','; COPY 1000000 Time: 7700.332 msPsycopg2 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:t_girl@127.0.0.1:5432/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:python_user@192.168.1.131:3306/t_girl?t1 INTO postgresql://t_girl:t_girl@127.0.0.1:5432/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:
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