cmdUnknown The type of command in the CommandText property is not known. cmdText CommandText is a textual definition of a command or stored procedure call; data returned by an internal SQL statement. cmdTable CommandText is the name of a table. cmdStoredProc CommandText is the name of a stored procedure. cmdFile CommandText is the name of a saved recordset file. cmdTableDirect CommandText is the name of a table; all columns are returned.
cmdText CommandText is a textual definition of a command or stored procedure call; data returned by an internal SQL statement.
cmdTable CommandText is the name of a table.
cmdStoredProc CommandText is the name of a stored procedure.
cmdFile CommandText is the name of a saved recordset file.
cmdTableDirect CommandText is the name of a table; all columns are returned.
TcommandType的属性值应该与CommandText 中所说明操作相一致,例如:当CommandText
属性的内容为数据表格名时,CommandType的属性值就应当为cmdTable或者是cmdTable
Direct.
TcommandType的默认值为cmdunknown,因为cmdunknown可以适用于所有操作.在
TcommandType中显式的指明操作的类型可以提高应用程序的运行速度,但如果将操作的类型
置为cmdunknown,ADO必须先判断操作的类型,这样就会减慢运行的速度.
注意在TcommandType属性值中包含的cmdTable,cmdTableDirect和cmdOpenFile不是
针对TADOCommand组件执行操作的.