Python - MySQL数据库相关对象及优化操作

Python数据库的Connection、Cursor两大对象

Python数据库图解流程

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参数优化

url
在url后加上参数rewriteBatchedStatements=true表示MySQL服务开启批次写入，此参数是批次写入的一个比较重要参数，可明显提升性能
batchsize
DataFrame writer批次写入MySQL的条数，也为提升性能的参数
isolationLevel
事务隔离级别，DataFrame写入不需要开启事务，为None
truncate
overwrite模式时可用，表示在覆盖原始数据的时候不会删除表结构而是复用

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Another

Python实现Java中的PrepareStatement功能

# import MySQL module
import MySQLdb
# get user input
name = raw_input("Please enter a name: ")
species = raw_input("Please enter a species: ")
# connect
db = MySQLdb.connect(host="localhost", user="joe", passwd="secret",db="db56a")
# create a cursor
cursor = db.cursor()
# execute SQL statement
cursor.execute("INSERT INTO animals (name, species) VALUES (%s, %s)",(name, species))

# import MySQL module
import MySQLdb
# connect
db = MySQLdb.connect(host="localhost", user="joe", passwd="secret",db="db56a")
# create a cursor
cursor = db.cursor()
# execute SQL statement
cursor.execute("""INSERT INTO test (field1, field2) VALUES ("val1","val2")""")
# get ID of last inserted record
print "ID of inserted record is ", int(cursor.insert_id())
# import MySQL module
import MySQLdb
# connect
db = MySQLdb.connect(host="localhost", user="joe", passwd="secret",db="db56a")
# create a cursor
cursor = db.cursor()
# dynamically generate SQL statements from  list
cursor.executemany("INSERT
INTO animals (name, species) VALUES (%s,%s)", [('Rollo', 'Rat'), 
('Dudley', 'Dolphin'),  ('Mark', 'Marmoset')])

# import MySQL module
import MySQLdb
# initialize some variables
name = ""
data = []
# loop and ask for user input
while (1):
name = raw_input("Please enter a name (EOF to end): ")
if name == "EOF":
break
species = raw_input("Please enter a species: ")
# put user input into a tuple
tuple = (name, species)
# and append to data[] list
data.append(tuple)
# connect
db = MySQLdb.connect(host="localhost", user="joe", passwd="secret",db="db56a")
# create a cursor
cursor = db.cursor()
# dynamically generate SQL statements from data[] list
cursor.executemany("INSERT INTO animals (name, species) VALUES (%s,%s)",data)