[PyQt]使用QSqlQuery操做Sql Server數據庫

測試數據庫名稱Test
測試表格名稱Person
字段Id：類型uniqueidentifier，默認值：newId()
字段Name：類型nvarchar(500)
字段Photo：類型varbinary(MAX)

#導入QtSql模塊
from PyQt5.QtSql import QSqlDatabase, QSqlQuery
from PyQt5.QtCore import QIODevice
from PyQt5.QtGui import QImage

#建立數據庫鏈接並打開（未指定數據庫名，建立默認鏈接）
db = QSqlDatabase.addDatabase("QODBC")
db.setDatabaseName("Driver={Sql Server};Server=localhost;Database=TEST;Uid=sa;Pwd=123456")
db.open()

#建立查詢對象（使用默認數據庫鏈接）
query = QSqlQuery()

#插入記錄並返回新記錄Id值
query.exec("INSERT INTO Person(Name) OUTPUT INSERTED.Id VALUES('Tom')")
query.next()
NewId = query.value("Id")

#刪除記錄，使用"?"操做符綁定值
query.prepare("DELETE FROM Person WHERE Name=?")
query.bindValue(0,"Tom")
query.exec_()                   #此處調用exec_()

#將圖片保存到數據庫，使用冒號佔位符
query.prepare("INSERT INTO Person(Name,Photo) VALUES(:N, :P)")

imagebytes = QByteArray()
buffer = QBuffer(imagebytes)
buffer.open(QIODevice.WriteOnly)
image = QImage(r"d:\test.jpg")
image.save(buffer,"JPG")
buffer.close()

query.bindValue(":N","張三")
query.bindValue(":P",imagebytes)
query.exec_()

#從數據庫載入圖片
query.prepare("SELECT Photo FROM Person WHERE Name=:Nm")
query.bindValue(":Nm","張三")
query.exec_()

query.next()
imagebytes = query.value("Photo")
buffer = QBuffer(imagebytes)
buffer.open(QIODevice.ReadOnly)
image = QImage()
image.load(buffer,"JPG")
buffer.close()