HANA CDS doesn't support type TINYINT
It seems to me that the Web IDE Editor doesn't seem recognize the TINYINT type in a CDS (.hdbdd) file. The text doesn't turn into blue color. Other type like INTEGER does turn into blue color. Do you see same issue? I am using SP8.
In the HANA Studio, when I check the .hdbdd file, it error out with message: can not find artifact "TINYINT". I tried "Tinyint", "TinyInt", "tinyInt" or "tinyint". None of them worked.
As you were not the only one asking for it - we opened up HANA CDS for the missing primitive data types: http://help.sap.com/saphelp_hanaplatform/helpdata/en/cf/394efd3fb4400f9c09d10315028515/content.htm (note the "hana" prefix!)