MySQL Shell import_table数据导入
1. import_table介绍
这一期我们介绍一款高效的数据导入工具,MySQL Shell 工具集中的import_table,该工具的全称是Parallel Table Import Utility,顾名思义,支持并发数据导入,该工具在MySQL Shell 8.0.23版本后,功能更加完善, 以下列举该工具的核心功能
- 基本覆盖了MySQL Data Load的所有功能,可以作为替代品使用
- 默认支持并发导入(支持自定义chunk大小)
- 支持通配符匹配多个文件同时导入到一张表(非常适用于相同结构数据汇总到一张表)
- 支持限速(对带宽使用有要求的场景,非常合适)
- 支持对压缩文件处理
- 支持导入到5.7及以上MySQL
2. Load Data 与 import table功能示例
该部分针对import table和Load Data相同的功能做命令示例演示,我们依旧以导入employees表的示例数据为例,演示MySQL Load Data的综合场景
- 数据自定义顺序导入
- 数据函数处理
- 自定义数据取值
示例数据如下：
[root@10-186-61-162 tmp]# cat employees_01.csv "10001","1953-09-02","Georgi","Facello","M","1986-06-26" "10003","1959-12-03","Parto","Bamford","M","1986-08-28" "10002","1964-06-02","Bezalel","Simmel","F","1985-11-21" "10004","1954-05-01","Chirstian","Koblick","M","1986-12-01" "10005","1955-01-21","Kyoichi","Maliniak","M","1989-09-12" "10006","1953-04-20","Anneke","Preusig","F","1989-06-02" "10007","1957-05-23","Tzvetan","Zielinski","F","1989-02-10" "10008","1958-02-19","Saniya","Kalloufi","M","1994-09-15" "10009","1952-04-19","Sumant","Peac","F","1985-02-18" "10010","1963-06-01","Duangkaew","Piveteau","F","1989-08-24"
示例表结构：
10.186.61.162:3306 employees SQL > desc emp;
+-------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------+------+-----+---------+-------+
| emp_no | int | NO | PRI | NULL | |
| birth_date | date | NO | | NULL | |
| first_name | varchar(14) | NO | | NULL | |
| last_name | varchar(16) | NO | | NULL | |
| full_name | varchar(64) | YES | | NULL | | -- 表新增字段,导出数据文件中不存在
| gender | enum("M","F") | NO | | NULL | |
| hire_date | date | NO | | NULL | |
| modify_date | datetime | YES | | NULL | | -- 表新增字段,导出数据文件中不存在
| delete_flag | varchar(1) | YES | | NULL | | -- 表新增字段,导出数据文件中不存在
+-------------+---------------+------+-----+---------+-------+
2.1 用Load Data方式导入数据
load data infile "/data/mysql/3306/tmp/employees_01.csv"
into table employees.emp
character set utf8mb4
fields terminated by ","
enclosed by """
lines terminated by "
"
(@C1,@C2,@C3,@C4,@C5,@C6)
set emp_no=@C1,
birth_date=@C2,
first_name=upper(@C3),
last_name=lower(@C4),
full_name=concat(first_name," ",last_name),
gender=@C5,
hire_date=@C6 ,
modify_date=now(),
delete_flag=if(hire_date<"1988-01-01","Y","N");
2.2 用import_table方式导入数据
util.import_table(
[
"/data/mysql/3306/tmp/employees_01.csv",
],
{
"schema": "employees",
"table": "emp",
"dialect": "csv-unix",
"skipRows": 0,
"showProgress": True,
"characterSet": "utf8mb4",
"columns": [1,2,3,4,5,6], ## 文件中多少个列就用多少个序号标识就行
"decodeColumns": {
"emp_no": "@1", ## 对应文件中的第1列
"birth_date": "@2", ## 对应文件中的第2个列
"first_name": "upper(@3)", ## 对应文件中的第3个列,并做转为大写的处理
"last_name": "lower(@4)", ## 对应文件中的第4个列,并做转为大写的处理
"full_name": "concat(@3," ",@4)", ## 将文件中的第3,4列合并成一列生成表中字段值
"gender": "@5", ## 对应文件中的第5个列
"hire_date": "@6", ## 对应文件中的第6个列
"modify_date": "now()", ## 用函数生成表中字段值
"delete_flag": "if(@6<"1988-01-01","Y","N")" ## 基于文件中第6列做逻辑判断,生成表中对应字段值
}
})
3. import_table特定功能
3.1 多文件导入(模糊匹配)
## 在导入前我生成好了3分单独的employees文件,导出的结构一致
[root@10-186-61-162 tmp]# ls -lh
总用量 1.9G
-rw-r----- 1 mysql mysql 579 3月 24 19:07 employees_01.csv
-rw-r----- 1 mysql mysql 584 3月 24 18:48 employees_02.csv
-rw-r----- 1 mysql mysql 576 3月 24 18:48 employees_03.csv
-rw-r----- 1 mysql mysql 1.9G 3月 26 17:15 sbtest1.csv
## 导入命令,其中对对文件用employees_*做模糊匹配
util.import_table(
[
"/data/mysql/3306/tmp/employees_*",
],
{
"schema": "employees",
"table": "emp",
"dialect": "csv-unix",
"skipRows": 0,
"showProgress": True,
"characterSet": "utf8mb4",
"columns": [1,2,3,4,5,6], ## 文件中多少个列就用多少个序号标识就行
"decodeColumns": {
"emp_no": "@1", ## 对应文件中的第1列
"birth_date": "@2", ## 对应文件中的第2个列
"first_name": "upper(@3)", ## 对应文件中的第3个列,并做转为大写的处理
"last_name": "lower(@4)", ## 对应文件中的第4个列,并做转为大写的处理
"full_name": "concat(@3," ",@4)", ## 将文件中的第3,4列合并成一列生成表中字段值
"gender": "@5", ## 对应文件中的第5个列
"hire_date": "@6", ## 对应文件中的第6个列
"modify_date": "now()", ## 用函数生成表中字段值
"delete_flag": "if(@6<"1988-01-01","Y","N")" ## 基于文件中第6列做逻辑判断,生成表中对应字段值
}
})
## 导入命令,其中对要导入的文件均明确指定其路径
util.import_table(
[
"/data/mysql/3306/tmp/employees_01.csv",
"/data/mysql/3306/tmp/employees_02.csv",
"/data/mysql/3306/tmp/employees_03.csv"
],
{
"schema": "employees",
"table": "emp",
"dialect": "csv-unix",
"skipRows": 0,
"showProgress": True,
"characterSet": "utf8mb4",
"columns": [1,2,3,4,5,6], ## 文件中多少个列就用多少个序号标识就行
"decodeColumns": {
"emp_no": "@1", ## 对应文件中的第1列
"birth_date": "@2", ## 对应文件中的第2个列
"first_name": "upper(@3)", ## 对应文件中的第3个列,并做转为大写的处理
"last_name": "lower(@4)", ## 对应文件中的第4个列,并做转为大写的处理
"full_name": "concat(@3," ",@4)", ## 将文件中的第3,4列合并成一列生成表中字段值
"gender": "@5", ## 对应文件中的第5个列
"hire_date": "@6", ## 对应文件中的第6个列
"modify_date": "now()", ## 用函数生成表中字段值
"delete_flag": "if(@6<"1988-01-01","Y","N")" ## 基于文件中第6列做逻辑判断,生成表中对应字段值
}
})
3.2 并发导入
在实验并发导入前我们创建一张1000W的sbtest1表(大约2G数据),做并发模拟,import_table用threads参数作为并发配置, 默认为8个并发.
## 导出测试需要的sbtest1数据
[root@10-186-61-162 tmp]# ls -lh
总用量 1.9G
-rw-r----- 1 mysql mysql 579 3月 24 19:07 employees_01.csv
-rw-r----- 1 mysql mysql 584 3月 24 18:48 employees_02.csv
-rw-r----- 1 mysql mysql 576 3月 24 18:48 employees_03.csv
-rw-r----- 1 mysql mysql 1.9G 3月 26 17:15 sbtest1.csv
## 开启threads为8个并发
util.import_table(
[
"/data/mysql/3306/tmp/sbtest1.csv",
],
{
"schema": "demo",
"table": "sbtest1",
"dialect": "csv-unix",
"skipRows": 0,
"showProgress": True,
"characterSet": "utf8mb4",
"threads": "8"
})
3.3 导入速率控制
可以通过maxRate和threads来控制每个并发线程的导入数据,如,当前配置线程为4个,每个线程的速率为2M/s,则最高不会超过8M/s
util.import_table(
[
"/data/mysql/3306/tmp/sbtest1.csv",
],
{
"schema": "demo",
"table": "sbtest1",
"dialect": "csv-unix",
"skipRows": 0,
"showProgress": True,
"characterSet": "utf8mb4",
"threads": "4",
"maxRate": "2M"
})
3.4 自定义chunk大小
默认的chunk大小为50M,我们可以调整chunk的大小,减少事务大小,如我们将chunk大小调整为1M,则每个线程每次导入的数据量也相应减少
util.import_table(
[
"/data/mysql/3306/tmp/sbtest1.csv",
],
{
"schema": "demo",
"table": "sbtest1",
"dialect": "csv-unix",
"skipRows": 0,
"showProgress": True,
"characterSet": "utf8mb4",
"threads": "4",
"bytesPerChunk": "1M",
"maxRate": "2M"
})
4. Load Data vs import_table性能对比
- 使用相同库表
- 不对数据做特殊处理,原样导入
- 不修改参数默认值,只指定必备参数
-- Load Data语句
load data infile "/data/mysql/3306/tmp/sbtest1.csv"
into table demo.sbtest1
character set utf8mb4
fields terminated by ","
enclosed by """
lines terminated by "
"
-- import_table语句
util.import_table(
[
"/data/mysql/3306/tmp/sbtest1.csv",
],
{
"schema": "demo",
"table": "sbtest1",
"dialect": "csv-unix",
"skipRows": 0,
"showProgress": True,
"characterSet": "utf8mb4"
})
可以看到,Load Data耗时约5分钟,而import_table则只要不到一半的时间即可完成数据导入,效率高一倍以上(虚拟机环境磁盘IO能力有限情况下)
以上就是MySQL Shell import_table数据导入详情的详细内容，更多关于import_table数据导入的资料请关注服务器之家其它相关文章！
原文链接：https://www.cnblogs.com/zhenxing/p/15102252.html
