1、将上述学生信息存入数据库中，表名为tb_score，读取该文件，用合适的数据类型存储文件内容，并打印输出所有内容。
1.首先创建数据库！
2.创建表
连接 StdDB数据库
config = {'host': 'localhost',
'port': 3306,
'user': 'root',
'passwd': '1414141',
'db' : 'StDB'
}
conn = pymysql.connect(**config)
执行 SQL 创建 表tb_score
cursor = conn.cursor()
sql = "CREATE TABLE tb_score(ID INT NOT NULL, name VARCHAR(20) NULL,score INT NULL, PRIMARY KEY (ID))"
cursor.execute(sql)
conn.close()将数据用多维列表方式存储在内存中
ls = []
ls.append([10001, "小明", 90])
ls.append([10002, "小白", 85])
ls.append([10003, "小兰", 83])
ls.append([10004, "小张", 92])
ls.append([10005, "小赵", 81])多条数据插入数据库中
cursor = conn.cursor()
sql = "insert into tb_score(ID,name,score) values({0},'{1}',{2})"
try:
for line in ls:
cursor.execute(sql.format(*line))
conn.commit()
except:
conn.rollback()
finally:
conn.close()读取数据库中数据
cursor = conn.cursor()
sql = "select * from tb_score"
cursor.execute(sql)
rows = cursor.fetchall()
ls2 = list(map(list, rows))
conn.close()
print(ls2)
（1）插入一条学生记录信息：学号：10006，姓名：小花，成绩：92
插入一条数据
ls3 = [10006, "小花", 92]
cursor = conn.cursor()
sql = "insert into tb_score(ID,name,score) values({0},'{1}',{2})"
try:
cursor.execute(sql.format(*ls3))
conn.commit()
except:
conn.rollback()
finally:
conn.close()
（2）打印输出学生成绩在90分以下的所有学生信息
根据条件读取数据库的信息
cursor = conn.cursor()
sql = "select ID,name,score from tb_score where score<{0}"
cursor.execute(sql.format(90))
rows = cursor.fetchall()
rows = list(map(list, rows))
print(rows)
（3）删除小明的成绩
删除数据库中的数据
cursor = conn.cursor()
sql = " delete from tb_score where name=%s "
try:
cursor.execute(sql, ["小明"])
conn.commit()
except:
conn.rollback()
实验题目：csv文件导入数据库
将StudentInfo.csv文件中的信息导入数据库StudentTest
import pymysql
# 连接 StudentTest数据库
config = {'host': 'localhost',
'port': 3306,
'user': 'root',
'passwd': '1414141',
'db' : 'StudentTest'，
'local_infile': 1
}
conn = pymysql.connect(**config)
# 执行 SQL 创建 表tb_student
cursor = conn.cursor()
sql = "CREATE TABLE tb_student(ID INT NOT NULL, name VARCHAR(20) NULL,score INT NULL,final INT NULL, PRIMARY KEY (ID))"
cursor.execute(sql)
conn.close()
# CSV数据高效导入 MYSQL
cursor = conn.cursor()
sql = " LOAD DATA LOCAL INFILE '{0}' INTO TABLE {1} CHARACTER SET GBK FIELDS TERMINATED BY ',' LINES TERMINATED BY '\\r\\n' IGNORE 1 LINES "
try:
cursor.execute(sql.format("D:/studentInfo.csv", "tb_student"))
conn.commit()
except Exception as e:
print(e)
conn.rollback()
cursor = conn.cursor()
sql = "select * from tb_student"
cursor.execute(sql)
rows = cursor.fetchall()
ls2 = list(map(list, rows))
conn.close()
print(ls2)
数据库导出到csv文件
数据库StudentTest中的信息导出到csvdata.csv文件中
import pymysql
# 连接 StudentTest数据库
config = {'host': 'localhost',
'port': 3306,
'user': 'root',
'passwd': '1414141',
'db' : 'StudentTest'，
'local_infile': 1
}
conn = pymysql.connect(**config)
cursor = conn.cursor()
sql = " select * into outfile '{0}' CHARACTER SET GBK FIELDS TERMINATED BY ',' LINES TERMINATED BY '\\r\\n' from(select '学号','姓名 ','平均成绩','期末成绩' union select * from tb_student) as b "
try:
cursor.execute(sql.format("D:/csvdata.csv",))
conn.commit()
except Exception as e:
print(e)
conn.rollback()
conn.close()
导出成功，查看CSV文件
出现‘The used command is not allowed with this MySQL version’错误
今天做实验时将csv数据导入数据库时出现‘The used command is not allowed with this MySQL version’错误，网上说是从本地导入文件的参数没有打开，在mysql.data升级之后，为了安全考虑，默认不允许加载本地文件数据。查找了好几个方法嫌麻烦，突然想起了老师原来讲过！
只需在连接数据库时添加local_infile：1就可以解决。
例如：
import pymysql
# 连接 StudentTest数据库
config = {'host': 'localhost',
'port': 3306,
'user': 'root',
'passwd': '12346',
'db' : 'StudentTest'
}
conn = pymysql.connect(**config)
CSV数据导入会出错！
import pymysql
# 连接 StudentTest数据库
config = {'host': 'localhost',
'port': 3306,
'user': 'root',
'passwd': '12346',
'db' : 'StudentTest'，
'local_infile': 1
}
conn = pymysql.connect(**config)
这样就不会出错了！
