A CIO is usually busy in sorting out IT infrastructure and enterprise apps availability. The skills are wholly focussed on availability of systems and to some extent data security from external breaches. The CDO need not bother about availability of IT systems, nor about cyber attacks.
A CTO in a telecom service company is a technologist who is primarily busy in imbibing new technology, rolling out services, getting teams trained to use the technology etc. These skills are very useful for the areas mentioned above but not enough for managing the company wide data.
Clear understanding of statistical concepts like statistical significance, Inferential statistics, null hypothesis, etc and can implement Machine Learning techniques to solve a prediction problem.
Understands techniques of mining large amounts of unstructured data.
Preferably in a data science language like
R or Python.
This separates the CDO from a generalist.
Can communicate and understand domain experts (e.g. telecommunication services). Since the CDO has to formulate strategies for feature engineering of datasets, domain knowledge of the operations and core business is extremely important.