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Hi!

I have following code which reads a blob value from mydb (datatype longblob, mysql 5.0, data size 512kB):

s = "SELECT fldBild FROM tblA WHERE fldID=1"
reader = g_DB.mySQLExecuteReader(s)
Do While reader.Read
blob = reader.GetMySqlBlob(0)
m_bytBild = blob.Value
Loop
reader.Close()

This works fine, but in some cases the program freezes in the line with reader.Read. CPU is at 0%, db process is on SLEEP state...

Please specify your .NET Framework version, MySQLDirect .NET version, MySQL version.
Post small peace of code and table definition to reproduce the problem.

NET Framework is 1.1
CoreLab Version is 3.20.5.0
MySQL is 5.0.16

Table definition:

CREATE TABLE `wunde_verlauf` (
`fldWundeVerlaufID` int(11) NOT NULL auto_increment,
`fldDatum` datetime default NULL,
`fldGroesse` text,
`fldKommentar` text,
`fldBild` mediumblob NOT NULL,
`fldWundbeschaffenheitRef` int(11) default NULL,
`fldWundeRef` int(11) default NULL,
`fldErsterWert` int(11) default NULL,
`fldUserRef` int(11) default NULL,
`fldAenderungsdatum` datetime default NULL,
`fldGeloescht` tinyint(4) default '0',
`fldIstLetzter` tinyint(4) default NULL,
PRIMARY KEY (`fldWundeVerlaufID`),
KEY `fldWundeRef` (`fldWundeRef`),
KEY `fldWundbeschaffenheitRef` (`fldWundbeschaffenheitRef`),
KEY `fldErsterWert` (`fldErsterWert`),
KEY `fldUserRef` (`fldUserRef`),
KEY `fldGeloescht` (`fldGeloescht`),
KEY `fldIstLetzter` (`fldIstLetzter`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1

Code fragment:
Dim s As String

Dim reader As MySqlDataReader

Dim blob As MySqlBlob

Dim cmd As new MySqlCommand

s = "SELECT fldBild FROM wunde_verlauf WHERE fldWundeVerlaufID=" & Me.WundeVerlaufID

openConnection(s)

cmd.Connection = m_dbConnection

cmd.CommandText = s

cmd.CommandType = CommandType.Text

the problem occurs only, if the blob data are larger than 16 kByte, independent on the table type

The problem was the compression of the connection object. When I disable compression, everything works fine.

I am using corelab.mysql.dll version 3.20.5.0, I thought this version could handle the compression feature???

We are investigating this problem right now.
You will be notified of the results

We have fixed this problem for the MySQLDirect .NET.
Look forward for the next build.