RMySQL数据库编程指南

通过R程序，读MySQL数据库数据

~ R

> library(RMySQL)
Loading required package: DBI

> conn <- dbConnect(MySQL(), dbname = "rmysql", username="rmysql", password="rmysql")
> users = dbGetQuery(conn, "SELECT * FROM t_user")
> dbDisconnect(conn)
[1] TRUE
> users
  id    user
1  1      A1
2  2      AB
3  3 fens.me

好了，我们实现了在Linux下R和MySQL的连接。

3. RMySQL在Win7下安装

Win系统环境：

• Win7: 64位 旗舰版
• Win字符集: gbk,utf8
• R: 3.0.1, x86_64-w64-mingw32/x64 (64-bit)
• MySQL: mysql Ver 14.14 Distrib 5.6.11, for Win64 (x86_64)

~ R --version
R version 3.0.1 (2013-05-16) -- "Good Sport"
Copyright (C) 2013 The R Foundation for Statistical Computing
Platform: x86_64-w64-mingw32/x64 (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under the terms of the
GNU General Public License versions 2 or 3.
For more information about these matters see
http://www.gnu.org/licenses/.

~ mysql --version
mysql  Ver 14.14 Distrib 5.6.11, for Win64 (x86_64)

mysql> show variables like ‘%char%‘;
+--------------------------+------------------------------------+
| Variable_name            | Value                              |
+--------------------------+------------------------------------+
| character_set_client     | gbk                                |
| character_set_connection | gbk                                |
| character_set_database   | utf8                               |
| character_set_filesystem | binary                             |
| character_set_results    | gbk                                |
| character_set_server     | utf8                               |
| character_set_system     | utf8                               |
| character_sets_dir       | D:\toolkit\mysql56\share\charsets\ |
+--------------------------+------------------------------------+
8 rows in set (0.07 sec)

在R环境中安装RMySQL

~ D:\workspace\R\mysql>R

> install.packages(‘RMySQl‘)
package ‘RMySQl‘ is not available (for R version 3.0.1)

我们看到提示，没有对应的RMySQL安装版本。

# 下载RMySQL源代码包
> install.packages("RMySQL", type="source")
URLhttp://cran.dataguru.cn/src/contrib/RMySQL_0.9-3.tar.gz‘
Content type ‘application/x-gzip‘ length 165363 bytes (161 Kb)
URL
downloaded 161 Kb

* installing *source* package ‘RMySQL‘ ...
** ‘RMySQL‘MD5
checking for $MYSQL_HOME... not found... searching registry...

cygwin warning:
  MS-DOS style path detected: C:/PROGRA~1/R/R-30~1.1/bin/x64/Rscript
  Preferred POSIX equivalent is: /cygdrive/c/PROGRA~1/R/R-30~1.1/bin/x64/Rscript
  CYGWIN environment variable option "nodosfilewarning" turns off this warning.
  Consult the user‘s guide for more details about POSIX paths:
    http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
readRegistry("SOFTWARE\\MySQL AB", hive = "HLM", maxdepth = 2) :
  Registry key ‘SOFTWARE\MySQL AB‘ not found

ERROR: configuration failed for package ‘RMySQL‘
* removing ‘C:/Program Files/R/R-3.0.1/library/RMySQL‘
        ‘C:\Users\Administrator\AppData\Local\Temp\RtmpsfqQjK\downloaded_packages‘

In install.packages("RMySQL", type = "source") :
  ‘RMySQL‘B0

找到源代码包：RMySQL_0.9-3.tar.gz

~ dir C:\Users\Administrator\AppData\Local\Temp\RtmpsfqQjK\downloaded_packages
2013-09-24  13:16           165,363 RMySQL_0.9-3.tar.gz

通过源代码包安装

~ D:\workspace\R\mysql>R CMD INSTALL C:\Users\Administrator\AppData\Local\Temp\RtmpsfqQjK\downloaded_packages\RMySQL_0.9-3
.tar.gz
* installing to library ‘C:/Program Files/R/R-3.0.1/library‘
* installing *source* package ‘RMySQL‘ ...
** ‘RMySQL‘MD5
checking for $MYSQL_HOME... not found... searching registry...

cygwin warning:
  MS-DOS style path detected: C:/PROGRA~1/R/R-30~1.1/bin/x64/Rscript
  Preferred POSIX equivalent is: /cygdrive/c/PROGRA~1/R/R-30~1.1/bin/x64/Rscript
  CYGWIN environment variable option "nodosfilewarning" turns off this warning.
  Consult the user‘s guide for more details about POSIX paths:
    http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
readRegistry("SOFTWARE\\MySQL AB", hive = "HLM", maxdepth = 2) :
  Registry key ‘SOFTWARE\MySQL AB‘ not found

ERROR: configuration failed for package ‘RMySQL‘
* removing ‘C:/Program Files/R/R-3.0.1/library/RMySQL‘

设置MYSQL_HOME的环境变量

set MYSQL_HOME=D:\toolkit\mysql56

注： MYSQL_HOME建议设置在系统环境变量中。

再一次安装RMySQL

D:\workspace\R\mysql>R CMD INSTALL C:\Users\Administrator\AppData\Local\Temp\RtmpsfqQjK\downloaded_packages\RMySQL_0.9-3
.tar.gz
* installing to library ‘C:/Program Files/R/R-3.0.1/library‘
* installing *source* package ‘RMySQL‘ ...
** ‘RMySQL‘MD5
checking for $MYSQL_HOME... D:\toolkit\mysql56
cygwin warning:
  MS-DOS style path detected: D:\toolkit\mysql56
  Preferred POSIX equivalent is: /cygdrive/d/toolkit/mysql56
  CYGWIN environment variable option "nodosfilewarning" turns off this warning.
  Consult the user‘s guide for more details about POSIX paths:
    http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
** libs
: this package has a non-empty ‘configure.win‘ file,
so building only the main architecture

cygwin warning:
  MS-DOS style path detected: C:/PROGRA~1/R/R-30~1.1/etc/x64/Makeconf
  Preferred POSIX equivalent is: /cygdrive/c/PROGRA~1/R/R-30~1.1/etc/x64/Makeconf
  CYGWIN environment variable option "nodosfilewarning" turns off this warning.
  Consult the user‘s guide for more details about POSIX paths:
    http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
gcc -m64 -I"C:/PROGRA~1/R/R-30~1.1/include" -DNDEBUG -I"D:\toolkit\mysql56"/include    -I"d:/RCompile/CRANpkg/extralibs6
4/local/include"     -O2 -Wall  -std=gnu99 -mtune=core2 -c RS-DBI.c -o RS-DBI.o
RS-DBI.c: In function ‘RS_na_set‘:
RS-DBI.c:1219:11: warning: variable ‘c‘ set but not used [-Wunused-but-set-variable]
gcc -m64 -I"C:/PROGRA~1/R/R-30~1.1/include" -DNDEBUG -I"D:\toolkit\mysql56"/include    -I"d:/RCompile/CRANpkg/extralibs6
4/local/include"     -O2 -Wall  -std=gnu99 -mtune=core2 -c RS-MySQL.c -o RS-MySQL.o
RS-MySQL.c: In function ‘RS_MySQL_fetch‘:
RS-MySQL.c:657:13: warning: variable ‘fld_nullOk‘ set but not used [-Wunused-but-set-variable]
RS-MySQL.c: In function ‘RS_DBI_invokeBeginGroup‘:
RS-MySQL.c:1137:30: warning: variable ‘val‘ set but not used [-Wunused-but-set-variable]
RS-MySQL.c: In function ‘RS_DBI_invokeNewRecord‘:
RS-MySQL.c:1158:20: warning: variable ‘val‘ set but not used [-Wunused-but-set-variable]
RS-MySQL.c: In function ‘RS_MySQL_dbApply‘:
RS-MySQL.c:1219:38: warning: variable ‘fld_nullOk‘ set but not used [-Wunused-but-set-variable]
gcc -m64 -shared -s -static-libgcc -o RMySQL.dll tmp.def RS-DBI.o RS-MySQL.o D:\toolkit\mysql56/bin/libmySQL.dll -Ld:/RC
ompile/CRANpkg/extralibs64/local/lib/x64 -Ld:/RCompile/CRANpkg/extralibs64/local/lib -LC:/PROGRA~1/R/R-30~1.1/bin/x64 -l
R
gcc.exe: error: D:\toolkit\mysql56/bin/libmySQL.dll: No such file or directory
ERROR: compilation failed for package ‘RMySQL‘
* removing ‘C:/Program Files/R/R-3.0.1/library/RMySQL‘

错误为没有找到动态链接库：D:\toolkit\mysql56/bin/libmySQL.dll

# 复制动态链接库libmySQL.dll
cp D:\toolkit\mysql56\lib\libmysql.dll D:\toolkit\mysql56\binmv D:\toolkit\mysql56\bin\libmysql.dll D:\toolkit\mysql56\bin\libmySQL.dll

再一次安装RMySQL

~ D:\workspace\R\mysql>R CMD INSTALL C:\Users\Administrator\AppData\Local\Temp\RtmpsfqQjK\downloaded_packages\RMySQL_0.9-3
.tar.gz
* installing to library ‘C:/Program Files/R/R-3.0.1/library‘
* installing *source* package ‘RMySQL‘ ...
** ‘RMySQL‘MD5
checking for $MYSQL_HOME... D:\toolkit\mysql56
cygwin warning:
  MS-DOS style path detected: D:\toolkit\mysql56
  Preferred POSIX equivalent is: /cygdrive/d/toolkit/mysql56
  CYGWIN environment variable option "nodosfilewarning" turns off this warning.
  Consult the user‘s guide for more details about POSIX paths:
    http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
** libs
: this package has a non-empty ‘configure.win‘ file,
so building only the main architecture

cygwin warning:
  MS-DOS style path detected: C:/PROGRA~1/R/R-30~1.1/etc/x64/Makeconf
  Preferred POSIX equivalent is: /cygdrive/c/PROGRA~1/R/R-30~1.1/etc/x64/Makeconf
  CYGWIN environment variable option "nodosfilewarning" turns off this warning.
  Consult the user‘s guide for more details about POSIX paths:
    http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
gcc -m64 -I"C:/PROGRA~1/R/R-30~1.1/include" -DNDEBUG -I"D:\toolkit\mysql56"/include    -I"d:/RCompile/CRANpkg/extralibs6
4/local/include"     -O2 -Wall  -std=gnu99 -mtune=core2 -c RS-DBI.c -o RS-DBI.o
RS-DBI.c: In function ‘RS_na_set‘:
RS-DBI.c:1219:11: warning: variable ‘c‘ set but not used [-Wunused-but-set-variable]
gcc -m64 -I"C:/PROGRA~1/R/R-30~1.1/include" -DNDEBUG -I"D:\toolkit\mysql56"/include    -I"d:/RCompile/CRANpkg/extralibs6
4/local/include"     -O2 -Wall  -std=gnu99 -mtune=core2 -c RS-MySQL.c -o RS-MySQL.o
RS-MySQL.c: In function ‘RS_MySQL_fetch‘:
RS-MySQL.c:657:13: warning: variable ‘fld_nullOk‘ set but not used [-Wunused-but-set-variable]
RS-MySQL.c: In function ‘RS_DBI_invokeBeginGroup‘:
RS-MySQL.c:1137:30: warning: variable ‘val‘ set but not used [-Wunused-but-set-variable]
RS-MySQL.c: In function ‘RS_DBI_invokeNewRecord‘:
RS-MySQL.c:1158:20: warning: variable ‘val‘ set but not used [-Wunused-but-set-variable]
RS-MySQL.c: In function ‘RS_MySQL_dbApply‘:
RS-MySQL.c:1219:38: warning: variable ‘fld_nullOk‘ set but not used [-Wunused-but-set-variable]
gcc -m64 -shared -s -static-libgcc -o RMySQL.dll tmp.def RS-DBI.o RS-MySQL.o D:\toolkit\mysql56/bin/libmySQL.dll -Ld:/RC
ompile/CRANpkg/extralibs64/local/lib/x64 -Ld:/RCompile/CRANpkg/extralibs64/local/lib -LC:/PROGRA~1/R/R-30~1.1/bin/x64 -l
R
installing to C:/Program Files/R/R-3.0.1/library/RMySQL/libs/x64
** R
** inst
** preparing package for lazy loading
Creating a generic function for ‘format‘ from package ‘base‘ in package ‘RMySQL‘
Creating a generic function for ‘print‘ from package ‘base‘ in package ‘RMySQL‘
** help
*** installing help indices
** building package indices
** installing vignettes
** testing if installed package can be loaded
MYSQL_HOME defined as D:\toolkit\mysql56
* DONE (RMySQL)

安装成功！

在MySQL中建库建表

~ mysql -uroot -p

mysql> create database rmysql;
Query OK, 1 row affected (0.04 sec)

mysql> grant all on rmysql.* to rmysql@‘%‘ identified by ‘rmysql‘;
Query OK, 0 rows affected (0.00 sec)

mysql> grant all on rmysql.* to rmysql@localhost identified by ‘rmysql‘;
Query OK, 0 rows affected (0.00 sec)

mysql> use rmysql
Database changed
mysql> CREATE TABLE t_user(
    -> id INT PRIMARY KEY AUTO_INCREMENT,
    -> user varchar(12) NOT NULL UNIQUE
    -> )ENGINE=INNODB DEFAULT CHARSET=utf8;
Query OK, 0 rows affected (1.01 sec)

mysql>
mysql> INSERT INTO t_user(user) values(‘A1‘),(‘AB‘),(‘fens.me‘);
Query OK, 3 rows affected (0.05 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> SELECT * FROM t_user;
+----+---------+
| id | user    |
+----+---------+
|  1 | A1      |
|  2 | AB      |
|  3 | fens.me |
+----+---------+
3 rows in set (0.03 sec)

通过R程序，读MySQL数据库数据。

注：如果刚才没有把MYSQL_HOME的变量写到环境变更中，每次在启动R之前要，先设置变量。

~ set MYSQL_HOME=D:\toolkit\mysql56
~ R

> library(RMySQL)
DBI
MYSQL_HOME defined as D:\toolkit\mysql56

> conn <- dbConnect(MySQL(), dbname = "rmysql", username="root", password="",client.flag=CLIENT_MULTI_STATEMENTS)
> users = dbGetQuery(conn, "SELECT * FROM t_user")
> dbDisconnect(conn)
[1] TRUE
> users
  id    user
1  1      A1
2  2      AB
3  3 fens.me

好了，我们实现了在Win7下R和MySQL的连接。

4. RMySQL函数使用

环境都安装好了，接下来我们具体使用一下RMySQL的包。

• RMySQL辅助操作
• RMySQL数据库操作
• 针对win的字符集设置

1). RMySQL辅助操作

加载类库

> library(RMySQL)

建立本地连接

> conn <- dbConnect(MySQL(), dbname = "rmysql", username="rmysql", password="rmysql",client.flag=CLIENT_MULTI_STATEMENTS)

建立远程连接

> conn <- dbConnect(MySQL(), dbname = "rmysql", username="rmysql", password="rmysql",host="192.168.1.201",port=3306)

关闭连接

dbDisconnect(conn)

查看数据库的表

> dbListTables(conn)
[1] "t_user"

查看表的字段

> dbListFields(conn, "t_user")
[1] "id"   "user"

查询MySQL信息

> summary(MySQL(), verbose = TRUE)
<MySQLDriver:(23864)> 
  Driver name:  MySQL 
  Max  connections: 16 
  Conn. processed: 3 
  Default records per fetch: 500 
  DBI API version:  

# MySQL连接实例信息
> summary(conn, verbose = TRUE)
<MySQLConnection:(23864,2)> 
  User: root 
  Host: localhost 
  Dbname: rmysql 
  Connection type: localhost via TCP/IP 
  MySQL server version:  5.6.11 
  MySQL client version:  5.6.11 
  MySQL protocol version:  10 
  MySQL server thread id:  35 
  No resultSet available

# MySQL连接信息
> dbListConnections(MySQL())
[[1]]
<MySQLConnection:(23864,2)> 

2). RMySQL数据库操作
RMySQL数据库操作

# 建表并插入数据
> t_demo<-data.frame(
  a=seq(1:10),
  b=letters[1:10],
  c=rnorm(10)
)
> dbWriteTable(conn, "t_demo", t_demo)

# 获得整个表数据
> dbReadTable(conn, "t_demo")
    a b           c
1   1 a  0.98868164
2   2 b -0.66935770
3   3 c  0.27703638
4   4 d  1.36137156
5   5 e -0.70291017
6   6 f  1.61235088
7   7 g  0.17616068
8   8 h  0.29700017
9   9 i  0.19032719
10 10 j -0.06222173

# 插入新数据
> dbWriteTable(conn, "t_demo", t_demo, append=TRUE)
> dbReadTable(conn, "t_demo")
   row_names  a b           c
1          1  1 a  0.98868164
2          2  2 b -0.66935770
3          3  3 c  0.27703638
4          4  4 d  1.36137156
5          5  5 e -0.70291017
6          6  6 f  1.61235088
7          7  7 g  0.17616068
8          8  8 h  0.29700017
9          9  9 i  0.19032719
10        10 10 j -0.06222173
11         1  1 a  0.98868164
12         2  2 b -0.66935770
13         3  3 c  0.27703638
14         4  4 d  1.36137156
15         5  5 e -0.70291017
16         6  6 f  1.61235088
17         7  7 g  0.17616068
18         8  8 h  0.29700017
19         9  9 i  0.19032719
20        10 10 j -0.06222173

# 覆盖原表数据
> dbWriteTable(conn, "t_demo", t_demo, overwrite=TRUE)

# 1). 查询数据
> d0 <- dbGetQuery(conn, "SELECT * FROM t_demo where c>0")
> class(d0)
[1] "data.frame"

> d0
  row_names a b         c
1         1 1 a 0.9886816
2         3 3 c 0.2770364
3         4 4 d 1.3613716
4         6 6 f 1.6123509
5         7 7 g 0.1761607
6         8 8 h 0.2970002
7         9 9 i 0.1903272

# 2). 执行SQL脚本查询，并分页
> rs <- dbSendQuery(conn, "SELECT * FROM t_demo where c>0")
> class(rs)
[1] "MySQLResult"
attr(,"package")
[1] "RMySQL"
> mysqlCloseResult(rs)
[1] TRUE

> d1 <- fetch(rs, n = 3)
> d1
  row_names a b         c
1         1 1 a 0.9886816
2         3 3 c 0.2770364
3         4 4 d 1.3613716

# 3). 查看集统计信息
> summary(rs, verbose = TRUE)
  row_names               a              b                   c         
 Length:7           Min.   :1.000   Length:7           Min.   :0.1762  
 Class :character   1st Qu.:3.500   Class :character   1st Qu.:0.2337  
 Mode  :character   Median :6.000   Mode  :character   Median :0.2970  
                    Mean   :5.429                      Mean   :0.7004  
                    3rd Qu.:7.500                      3rd Qu.:1.1750  
                    Max.   :9.000                      Max.   :1.6124

# 不插入row.names字段
> dbWriteTable(conn, "t_demo", t_demo,row.names=FALSE,overwrite=TRUE)
> dbGetQuery(conn, "SELECT * FROM t_demo where c>0")
  a b         c
1 1 a 0.9886816
2 3 c 0.2770364
3 4 d 1.3613716
4 6 f 1.6123509
5 7 g 0.1761607
6 8 h 0.2970002
7 9 i 0.1903272

# 删除表
> if(dbExistsTable(conn,‘t_demo‘)){
+     dbRemoveTable(conn, "t_demo")
+ }
[1] TRUE

执行SQL语句，dbSendQuery

> query<-dbSendQuery(conn, "show tables")
> data <- fetch(query, n = -1)
> data
  Tables_in_rmysql
1           t_demo
2           t_user
> mysqlCloseResult(query)
[1] TRUE

4). win的字符集设置
在win7中，向MySQL插入中文

mysql> INSERT INTO t_user(user) values(‘小朋友‘),(‘你好‘),(‘正确了‘);
Query OK, 3 rows affected (0.07 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> select * from t_user;
+----+---------+
| id | user    |
+----+---------+
|  1 | A1      |
|  2 | AB      |
|  3 | fens.me |
|  5 | 你好    |
|  4 | 小朋友  |
|  6 | 正确了  |
+----+---------+
6 rows in set (0.07 sec)

通过RMySQL查询

> dbGetQuery(conn, "SELECT * FROM t_user")
  id    user
1  1      A1
2  2      AB
3  3 fens.me
4  5      ??
5  4     ???
6  6     ???

设置GKB字符集

> dbDisconnect(conn)
> conn <- dbConnect(MySQL(), dbname = "rmysql", username="root", password="",client.flag=CLIENT_MULTI_STATEMENTS)
> dbSendQuery(conn,‘SET NAMES gbk‘)
<mysqlresult:(23864,43,2)> 
> query<-dbSendQuery(conn, "SELECT * FROM t_user")
> data <- fetch(query, n = -1)
> mysqlCloseResult(query)
[1] TRUE
> data
  id    user
1  1      A1
2  2      AB
3  3 fens.me
4  5    你好
5  4  小朋友
6  6  正确了

OK，我们在win下面修正字符编号的问题。

5. RMySQL案例实践

系统需求描述：Linux MySQL，Win7的R环境，远程连接

• 1. 通过SQL新建表t_blog，主键索引，唯一键索引
• 2. 用RMySQL插入数据，包括中文字段
• 3. 再用RMySQL取出数据

1). 通过SQL新建表t_blog，主键索引，唯一键索引
建表语句

CREATE TABLE t_blog(
id INT PRIMARY KEY AUTO_INCREMENT,
title varchar(12) NOT NULL UNIQUE,
author varchar(12) NOT NULL, 
length int NOT NULL,
create_date timestamp NOT NULL DEFAULT now()
)ENGINE=INNODB DEFAULT CHARSET=UTF8;

mysql> desc t_blog;
+-------------+-------------+------+-----+-------------------+----------------+
| Field       | Type        | Null | Key | Default           | Extra          |
+-------------+-------------+------+-----+-------------------+----------------+
| id          | int(11)     | NO   | PRI | NULL              | auto_increment |
| title       | varchar(12) | NO   | UNI | NULL              |                |
| author      | varchar(12) | NO   |     | NULL              |                |
| length      | int(11)     | NO   |     | NULL              |                |
| create_date | timestamp   | NO   |     | CURRENT_TIMESTAMP |                |
+-------------+-------------+------+-----+-------------------+----------------+
5 rows in set (0.00 sec)

mysql> show indexes from t_blog;
+--------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table  | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+--------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| t_blog |          0 | PRIMARY  |            1 | id          | A         |           3 |     NULL | NULL   |      | BTREE      |         |               |
| t_blog |          0 | title    |            1 | title       | A         |           3 |     NULL | NULL   |      | BTREE      |         |               |
+--------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
2 rows in set (0.00 sec)


INSERT INTO t_blog(title,author,length) values(‘你好，第一篇‘,‘Conan‘,20),(‘RMySQL数据库编程‘,‘Conan‘,99),(‘R的极客理想系列文章‘,‘Conan‘,15);

mysql> select * from t_blog;
+----+------------------------------+--------+--------+---------------------+
| id | title                        | author | length | create_date         |
+----+------------------------------+--------+--------+---------------------+
|  1 | 你好，第一篇                 | Conan  |     20 | 2013-08-15 00:13:13 |
|  2 | RMySQL数据库编程             | Conan  |     99 | 2013-08-15 00:13:13 |
|  3 | R的极客理想系列文章          | Conan  |     15 | 2013-08-15 00:13:13 |
+----+------------------------------+--------+--------+---------------------+
3 rows in set (0.00 sec)

2). 用RMySQL插入数据，包括中文字段，再取出数据

> library(RMySQL)
> conn <- dbConnect(MySQL(), dbname = "rmysql", username="rmysql", password="rmysql",host="192.168.1.201",port=3306)
> 
> dbSendQuery(conn,‘SET NAMES gbk‘)
<mysqlresult:(23864,49,0)> 
> dbSendQuery(conn,"INSERT INTO t_blog(title,author,length) values(‘R插入的新文章‘,‘Conan‘,50)");
<mysqlresult:(23864,49,1)> 
> 
> query<-dbSendQuery(conn, "SELECT * FROM t_blog")
Warning message:
In mysqlExecStatement(conn, statement, ...) :
  RS-DBI driver warning: (unrecognized MySQL field type 7 in column 4 imported as character)
> data <- fetch(query, n = -1)
> mysqlCloseResult(query)
[1] TRUE
> print(data)
  id               title author length         create_date
1  1        你好，第一篇  Conan     20 2013-08-15 00:13:13
2  2    RMySQL数据库编程  Conan     99 2013-08-15 00:13:13
3  3 R的极客理想系列文章  Conan     15 2013-08-15 00:13:13
4  4       R插入的新文章  Conan     50 2013-08-15 00:29:45
> 
> dbDisconnect(conn)
[1] TRUE

特别提示，不能用dbWriteTable函数！

RMySQL数据库编程指南

标签：linu   shell   nali   3.0   object   启动   lan   path   pack   

本文系统来源：http://www.cnblogs.com/awishfullyway/p/6668264.html

内容总结

以上是互联网集市为您收集整理的RMySQL数据库编程指南全部内容，希望文章能够帮你解决RMySQL数据库编程指南所遇到的程序开发问题。 如果觉得互联网集市技术教程内容还不错，欢迎将互联网集市网站推荐给程序员好友。

内容备注

版权声明：本文内容由互联网用户自发贡献，该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容， 请发送邮件至 gblab@vip.qq.com 举报，一经查实，本站将立刻删除。

内容手机端