In Access, the Mid function returns a string containing a specified number of characters from a string.
The syntax for the Mid function is:
Mid( (string, start [, length]) )
string String expression from which another string is created. This can be any string expression. If string contains Null, Null is returned.
start Long expression that indicates the character position in string at which the part to be taken begins. If start is greater than the number of characters in string, Mid returns a zero-length string ("").
length Long expression that indicates the number of characters to return. If omitted or if there are fewer than length characters in the text (including the character at start), all characters from the start position to the end of the string are returned.