在使用ASP連接MySQL數(shù)據(jù)庫(kù)獲取大量數(shù)據(jù)時(shí)，可能會(huì)遇到以下報(bào)錯(cuò)信息：

[MySQL][ODBC 5.3(a) Driver][mysqld-8.0.27]Commands out of sync; you can't run this command now

這是因?yàn)樵讷@取MySQL數(shù)據(jù)時(shí)，ASP會(huì)將數(shù)據(jù)存儲(chǔ)在緩存中，當(dāng)數(shù)據(jù)量過(guò)大時(shí)，緩存會(huì)被占滿，從而導(dǎo)致該錯(cuò)誤。

解決該問(wèn)題有如下兩種方法：

1. 增加緩存大小

Set conn = Server.CreateObject("ADODB.Connection")
conn.ConnectionString = "DRIVER={MySQL ODBC 5.3 Driver}; SERVER=localhost; DATABASE=mydb; UID=myuser; PASSWORD=mypassword; OPTION=3"
conn.Open
conn.Execute "SET SESSION query_cache_size=268435456;"

通過(guò)修改MySQL查詢緩存大小，可以增加緩存的空間，從而減少該錯(cuò)誤出現(xiàn)的概率。

2. 使用多個(gè)連接獲取數(shù)據(jù)

Function GetData()
Dim conn, cmd, rs
Set conn = Server.CreateObject("ADODB.Connection")
conn.ConnectionString = "DRIVER={MySQL ODBC 5.3 Driver}; SERVER=localhost; DATABASE=mydb; UID=myuser; PASSWORD=mypassword; OPTION=3"
conn.Open
Set cmd = Server.CreateObject("ADODB.Command")
cmd.ActiveConnection = conn
cmd.CommandText = "SELECT * FROM mytable"
Set rs = Server.CreateObject("ADODB.Recordset")
rs.CursorLocation = adUseServer
rs.Open cmd, , adOpenForwardOnly, adLockReadOnly
Do While Not rs.EOF
'處理數(shù)據(jù)
rs.MoveNext
Loop
rs.Close
Set rs = Nothing
Set cmd = Nothing
conn.Close
Set conn = Nothing
End Function

使用多個(gè)連接可以將數(shù)據(jù)分批獲取，從而減少緩存被占滿的情況出現(xiàn)。