Python Learning Seventh SQL optimization

Querying a single statement: Used to get a list of users and individual users

>>> fields=["id", "name", "NAME_CN", "email", "mobile"]                 >>> sql= "select %s from  users where name = ' admin '  %  ', '. Join (Fields) >>> sql "Select id, name,name_cn,email,mobile from users where name = ' admin ' >>>  Cur.execute (SQL) 1l>>> res=cur.fetchone () >>> res (16l, u ' admin ',  u ' admin ',  u ' 134556 ',  u ' 123455 ') >>> user={}>>> for i,k in enumerate (fields): ...     user[k]=res[i]... >>> user{' mobile ':  u ' 123455 ',   ' email ':  u ' 134556 ',  ' name_cn ':  u ' admin ',  ' id ': 16l,  ' name ':  u ' admin '} >>> for i,k in enumerate (Fields): ...      print i,k    i  is the index value, K is the FThe value inside the ields  ...  0 id1 name2 name_cn3 email4 mobile>>> res[1]u ' Admin

Insert statement: Add user

Version 1.0

>>> fields=["id", "name", "NAME_CN", "email", "mobile", "role" >>> fields[' id ', ' name ', ' name_cn ', ' Email ', ' mobile ', ' role ']>>> sql= ' insert into users (%s) values (' Fujinzhou ', ' Fujinzhou ', ' [email protected] ', ' 136** ', ' Ops ') "% ', '. Join (fields) >>> SQL" INSERT into users (id,name,name_cn,email,mobile,role) VALUES (' Fujinzhou ', ' Fujinzhou ', ' [email protected] ', ' 136** ', ' Ops ')

Version 2.0

>>> fields=["name", "NAME_CN", "email", "mobile", "role" >>> data={"name": "Fujinzhou"}>>> data{' name ': ' Fujinzhou '}>>> data={"name": "Fujinzhou", "NAME_CN": "Fujinzhou", "email": "[email protected]", "Mobile": "1122", "Role": "Ops"}>>> sql= "insert into users (%s) values%s"% (', '. Join (Fields), ', '. Join ([' "'%s '% DATA[K]) >>> SQL ' insert into users (name,name_cn,email,mobile,role) values "Fujinzhou", " Fujinzhou "," [email protected] "," 1122 "," Ops "

Version 3.0

>>> fields=[]>>> values=[]>>> data={"name": "Fujinzhou", "NAME_CN": "Fujinzhou", "email": "[ Email protected] "," mobile ":" 1122 "," Role ":" Ops "} >>> for K,v in Data.items (): ... fields.append (k) ... Valu Es.append ("'%s '"% v) ... >>> fields[' mobile ', ' role ', ' name_cn ', ' name ', ' email ']>>> values[' ' 1122 ', "' Ops '", "' Fujinzhou '", "' Fujinzhou '", "' [email protected] '"]>>> sql= "insert into users (%s) values (%s)"% (', '. Join (Fields), ', '. Join (values) >>> SQL "INSERT into users (Mobile,role,name_cn,name,email) VALUES (' 1122 ', ' Ops ', ' Fujinzhou ', ' Fujinzhou ', ' [email protected] '

This article from "Do not abandon!" Do not give up "blog, declined reprint!"

Python learning seventh SQL optimization