Oracle 5.0, Справочное руководство

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Connector/Net Programming
1911
Imports System.Text
Imports System.Data
Imports MySql.Data
Imports MySql.Data.MySqlClient
Module Module1
Sub Main()
Dim conn As New MySqlConnection()
conn.ConnectionString = "server=localhost;user=root;database=world;port=3306;password=******;"
Dim cmd As New MySqlCommand()
Try
Console.WriteLine("Connecting to MySQL...")
conn.Open()
cmd.Connection = conn
cmd.CommandText = "DROP PROCEDURE IF EXISTS add_emp"
cmd.ExecuteNonQuery()
cmd.CommandText = "DROP TABLE IF EXISTS emp"
cmd.ExecuteNonQuery()
cmd.CommandText = "CREATE TABLE emp (empno INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY, first_name VARCHAR(20), last_name VARCHAR(20), birthdate DATE)"
cmd.ExecuteNonQuery()
cmd.CommandText = "CREATE PROCEDURE add_emp(" & "IN fname VARCHAR(20), IN lname VARCHAR(20), IN bday DATETIME, OUT empno INT)" & "BEGIN INSERT INTO emp(first_name, last_name, birthdate) " & "VALUES(fname, lname, DATE(bday)); SET empno = LAST_INSERT_ID(); END"
cmd.ExecuteNonQuery()
Catch ex As MySqlException
Console.WriteLine(("Error " & ex.Number & " has occurred: ") + ex.Message)
End Try
conn.Close()
Console.WriteLine("Connection closed.")
Try
Console.WriteLine("Connecting to MySQL...")
conn.Open()
cmd.Connection = conn
cmd.CommandText = "add_emp"
cmd.CommandType = CommandType.StoredProcedure
cmd.Parameters.AddWithValue("@lname", "Jones")
cmd.Parameters("@lname").Direction = ParameterDirection.Input
cmd.Parameters.AddWithValue("@fname", "Tom")
cmd.Parameters("@fname").Direction = ParameterDirection.Input
cmd.Parameters.AddWithValue("@bday", "1940-06-07")
cmd.Parameters("@bday").Direction = ParameterDirection.Input
cmd.Parameters.AddWithValue("@empno", MySqlDbType.Int32)
cmd.Parameters("@empno").Direction = ParameterDirection.Output
cmd.ExecuteNonQuery()
Console.WriteLine("Employee number: " & cmd.Parameters("@empno").Value)
Console.WriteLine("Birthday: " & cmd.Parameters("@bday").Value)
Catch ex As MySql.Data.MySqlClient.MySqlException
Console.WriteLine(("Error " & ex.Number & " has occurred: ") + ex.Message)
End Try
conn.Close()
Console.WriteLine("Done.")
End Sub
End Module
20.2.5.10. Handling BLOB Data With Connector/Net
One common use for MySQL is the storage of binary data in
BLOB
columns. MySQL supports
four different BLOB data types:
TINYBLOB
,
BLOB
,
MEDIUMBLOB
, and
LONGBLOB
, all described in
Section 11.1.6.3, “The
BLOB
and
TEXT
Types” and Section 11.2, “Data Type Storage Requirements” .