python連接,操作pgsql

Python連接,操作PGSQL

1.安裝python

• Mac上 brew install python
• linux上 apt-get install python

2.安裝psycopg2

• 在 https://pypi.python.org/pypi/psycopg2/下載psycopg2 2.6.1
• 解壓後進入文件夾psycopg2 2.6.1
• 輸入命令 sudo python setup.py install

3.連接PGSQL,python代碼

    import psycopg2
    conn = psycopg2.connect(database="testdb", user="postgres", password="pass123", host="127.0.0.1", port="5432")
    print "Opened database successfully"  

4.創建表

    import psycopg2

    conn = psycopg2.connect(database="testdb", user="postgres", password="pass123", host="127.0.0.1", port="5432")
    print "Opened database successfully"

    cur = conn.cursor()
    cur.execute('''CREATE TABLE COMPANY
           (ID INT PRIMARY KEY     NOT NULL,
           NAME           TEXT    NOT NULL,
           AGE            INT     NOT NULL,
           ADDRESS        CHAR(50),
           SALARY         REAL);''')
    print "Table created successfully"

    conn.commit()
    conn.close()  

5.INSERT 操作

    import psycopg2

    conn = psycopg2.connect(database="testdb", user="postgres", password="pass123", host="127.0.0.1", port="5432")
    print "Opened database successfully"

    cur = conn.cursor()

    cur.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
          VALUES (1, 'Paul', 32, 'California', 20000.00 )");

    cur.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
          VALUES (2, 'Allen', 25, 'Texas', 15000.00 )");

    cur.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
          VALUES (3, 'Teddy', 23, 'Norway', 20000.00 )");

    cur.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
          VALUES (4, 'Mark', 25, 'Rich-Mond ', 65000.00 )");

    conn.commit()
    print "Records created successfully";
    conn.close() yiibai.com     

6.SELECT 操作

    import psycopg2

    conn = psycopg2.connect(database="testdb", user="postgres", password="pass123", host="127.0.0.1", port="5432")
    print "Opened database successfully"

    cur = conn.cursor()

    cur.execute("SELECT id, name, address, salary  from COMPANY")
    rows = cur.fetchall()
    for row in rows:
       print "ID = ", row[0]
       print "NAME = ", row[1]
       print "ADDRESS = ", row[2]
       print "SALARY = ", row[3], "\n"

    print "Operation done successfully";
    conn.close()  

7.UPDATE 操作

    import psycopg2

    conn = psycopg2.connect(database="testdb", user="postgres", password="pass123", host="127.0.0.1", port="5432")
    print "Opened database successfully"

    cur = conn.cursor()

    cur.execute("UPDATE COMPANY set SALARY = 25000.00 where ID=1")
    conn.commit
    print "Total number of rows updated :", cur.rowcount

    cur.execute("SELECT id, name, address, salary  from COMPANY")
    rows = cur.fetchall()
    for row in rows:
       print "ID = ", row[0]
       print "NAME = ", row[1]
       print "ADDRESS = ", row[2]
       print "SALARY = ", row[3], "\n"

    print "Operation done successfully";
    conn.close() 

8.DELETE 操作

     import psycopg2

    conn = psycopg2.connect(database="testdb", user="postgres", password="pass123", host="127.0.0.1", port="5432")
    print "Opened database successfully"

    cur = conn.cursor()

    cur.execute("DELETE from COMPANY where ID=2;")
    conn.commit
    print "Total number of rows deleted :", cur.rowcount

    cur.execute("SELECT id, name, address, salary  from COMPANY")
    rows = cur.fetchall()
    for row in rows:
       print "ID = ", row[0]
       print "NAME = ", row[1]
       print "ADDRESS = ", row[2]
       print "SALARY = ", row[3], "\n"

    print "Operation done successfully";
    conn.close()