0x00 byte problem while storing binary data to MySQL BLOB via ODBC (C API)

[whitesail]

Have a data truncation problem at NULL byte, while trying to store binary array to BLOB Table 'major' structure is: (smallint) Frame_number|(longblob) ch1|(longblob) ch2|(longblob) ch3|(longblob) ch4|(smallint) frame_size
Connection to base is done, memory for all necessary handles is allocated. 1. Prepare statemt

SQLPrepare(sql_hStmt,_T("INSERT INTO major(Frame_number,CH1,CH2,CH3,CH4,frame_size) VALUES(?,?,?,?,?,?)"),SQL_NTS);

2. Binding params

SQLBindParameter(sql_hStmt, 1, SQL_PARAM_INPUT, SQL_INTEGER, SQL_INTEGER, 0,0, &frames_parsed, 0, 0);
SQLBindParameter(sql_hStmt, 2, SQL_PARAM_INPUT, SQL_C_BINARY, SQL_VARBINARY, 0,0, v, bufsz, 0);
SQLBindParameter(sql_hStmt, 3, SQL_PARAM_INPUT, SQL_C_BINARY, SQL_VARBINARY, 0,0, v, bufsz, 0);
SQLBindParameter(sql_hStmt, 4, SQL_PARAM_INPUT, SQL_C_BINARY, SQL_VARBINARY, 0,0, v, bufsz, 0);
SQLBindParameter(sql_hStmt, 5, SQL_PARAM_INPUT, SQL_C_BINARY, SQL_VARBINARY, 0,0, v, bufsz, 0);
SQLBindParameter(sql_hStmt, 6, SQL_PARAM_INPUT, SQL_INTEGER, SQL_INTEGER, 0,0, &datasize, 0, 0);

where v - array holding data to be stored to DB. bufsz - its size 3. Cycle execution

SQLExecute(sql_hStmt);

Ant suggestion would be great, thanks. ver MySQL - 5.5, ver OBDC - Mysql ODBC 5.1

[Blue_Boy]

First check parameter value for null or empty content, if is null then send DBNull value (in .NET is DBNull.Value) , if is not null then send value of array. Hope this will help you :)

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[whitesail]

Hi! Thanks, that was helpful, but only partly, since passing SQL_NULL_DATA (-1) instead of 0x00, I get 0xFF value in the base field. if (v[i] == 0x00) v[i] = SQL_NULL_DATA; How do I later distingush real FF bytes from wraped null data? :sigh: Still many thanks for help