使用Python DB-API连接InterSystems IRIS

InterSystems IRIS 允许从任何符合DB-API的Python应用程序对InterSystems IRIS 进行快速、无缝地访问。Python DB-API驱动是对PEP 249 v2.0（Python数据库API规范 v2.0）的完整兼容。

步骤

1. 前提是要有一个Python的开发环境。
   本示例使用vs code 如下所示创建一个dbapi.py文件。
   dbapi.py :

   # Embedded Python examples from summer 2022
   import iris as dbapi
   ​
   mytable = "mypydbapi.test_things"
   conn = dbapi.connect(hostname='localhost', port=1972, namespace='IRISAPP', username='superuser', password='iris')
   ​
   # Create table
   cursor = conn.cursor()
   try:
    cursor.execute(f"CREATE TABLE {mytable} (myvarchar VARCHAR(255), myint INTEGER, myfloat FLOAT)")
   except Exception as inst:
    pass
   cursor.close()
   conn.commit()
   ​
   # Create some data to fill in
   chunks = []
   paramSequence = []
   for row in range(10):
    paramSequence.append(["This is a non-selective string every row is the same data", row%10, row * 4.57292])
    if (row>0 and ((row % 10) == 0)):
      chunks.append(paramSequence)
      paramSequence = []
   chunks.append(paramSequence)
   ​
   query = f"INSERT INTO {mytable} (myvarchar, myint, myfloat) VALUES (?, ?, ?)"
   ​
   for chunk in chunks:
    cursor = conn.cursor()
    cursor.executemany(query, chunk)
    cursor.close()
    conn.commit()
   # conn.close()
   ​
   sql = f"select * from {mytable}"
   rowsRead = 0
   cursor = conn.cursor()
   cursor.arraysize = 20
   ​
   cursor.execute(sql)
   rc = cursor.rowcount
   rows = cursor.fetchall()
   for row in rows:
    print(row)
   rowsRead += len(rows)
   ​
   cursor.close()
   conn.close()

2. 安装 DB-API驱动，点击此链接下载DB-API驱动
   

   pip install intersystems_irispython-version-py3-none-any.whl

3. 配置Connection String - 按照Intersystems IRIS的服务器，在dbapi.py文件中配置
   
   • hostname
   • port
   • namespace
   • username
   • password

4. 在InterSystems IRIS管理门户中创建IRISAPP命名空间。
5. 在VS code中运行dbapi.py文件，运行结果如下，说明数据成功导入。
   

   ['This is a non-selective string every row is the same data', 0, 0.0]
   ['This is a non-selective string every row is the same data', 1, 4.57292]
   ['This is a non-selective string every row is the same data', 2, 9.14584]
   ['This is a non-selective string every row is the same data', 3, 13.71876]
   ['This is a non-selective string every row is the same data', 4, 18.29168]
   ['This is a non-selective string every row is the same data', 5, 22.8646]
   ['This is a non-selective string every row is the same data', 6, 27.43752]
   ['This is a non-selective string every row is the same data', 7, 32.01044]
   ['This is a non-selective string every row is the same data', 8, 36.58336]
   ['This is a non-selective string every row is the same data', 9, 41.156279999999995]

6. 在IRISAPP命名空间下，查看InterSystems IRIS 数据库，可以看到数据，说明数据导入成功InterSystems IRIS。
   

   SELECT myvarchar, myint, myfloat FROM mypydbapi.test_things