Descriptive research is often said to take a deductive approach and is quantitative in nature. Can it also be inductive when little is know about the topic? Is there not a contradiction then? I am a novice market researcher who loves philosophy but I am getting lost a bit..
It seems to me like you're asking about social science methodology, rather than the philosophical use of these terms. Let's start with three important distinctions:
quantitative / qualitative: Quantitative research uses numeric data. These could be numeric measurements (e.g., the number of people working in a particular industry or living in a particular place) or numerical representations of non-numerical phenomena (e.g., asking people whether they like or dislike Trump and representing the responses as 1 or 0). Qualitative research uses non-numeric data. Often these data are transcripts of conversations, between the people being studied or during interviews. Mixed-methods social science research uses both quantitative and qualitative data. Recent work in computational social science often applies computational methods to qualitative data, such as text mining.
observational / experimental: Observational research gathers data with no/minimal/no intended influence on the people or situation under study. Experimental research makes deliberately intervenes on the people or situation under study, in order to understand the effects of that intervention.
inductive / deductive: As these terms are used by social scientists, deductive research uses a more-or-less well-developed and articulated theory to collect data and interpret it. In statistics, this is often called "confirmatory research": there's a clearly-stated hypothesis, and the aim of the study is to confirm (or disconfirm) it. Inductive research doesn't have a well-developed or articulated theory. Often this looks like what statisticians call "exploratory research": the researchers gather some data, then examine it for patterns, trying to identify phenomena and usually suggest a potential hypothesis that might explain it.
Note that philosophers use the terms "inductive" and "deductive" differently. Specifically, in logic, deductive arguments (attempt to) guarantee the truth of their conclusions, given the premises; they provide certainty. Inductive arguments don't offer this kind of guarantee. Deductive methods used by social scientists will often be inductive in the philosophers' sense: the assumptions of the theory don't guarantee that the data must be analyzed in a certain way. And exploratory data analysis (an inductive method, in the social scientists' sense) involves mathematical analysis of data, which is deductive in the philosophers' sense.
To respond to your question, these three pairs of distinctions are independent. You can have qualitative, observational, deductive research; or qualitative, observational, inductive research; or quantitative, experimental, inductive research; and so on. Specifically, observational research (what you call "descriptive research") can be quantitative and deductive. But it could also be quantitative and inductive. Or qualitative and deductive. Or qualitative and inductive.