I’ve watched very few Next Gens, but I saw a couple with some curley-haired blonde lady doctor who was a complete bitch (it wasn’t the good-looking redhead doctor who was Wesley’s mom)–and kept talking about how fun it would be to dissect Data. I kept wondering “Where’s Starfleet’s HR department. How is this kind of abuse allowed? And for that matter, why did they keep her on the ship?”
Was that ever resolved?
Dr. Pulaski link
I guess she was not likable enough for the fans.
Edit: She seems to be the female version of McCoy. Fear of transporter. Fascinated with teasing the Spock analog (Data). Cynical, a little gruff around the edges. The fans may have preferred Crusher’s more soft spoken bedside manner.
Engineering/Operations, yes. I don’t know of any flashbacks showing him earlier than the first episode of ST:TNG, let alone in anything other than the mustard yellow E/O uniform.
Data was usually a fun and interesting character, and well-played by Brent Spiner, but several things about him just don’t add up. How hard would it be to add a “Appropriate use of contractions in speech” subroutine? Why did he seem stuck at the rank of lieutenant commander for so long? Why did his appearance change so much over the years?
Yes, I’m a nitpicker.
I liked her well enough to have married a woman who could be her younger sister. 
Speaking of contractions, he did slip up and use them a few times. I would wager that he actually used them slightly more than Worf. Now there is a man of few contractions.
He used a contraction in the first episode. “At least we’re acquainted with the judge.”
A Klingon does not contract. It is not honorable.
When Data first mentioned that he went to the Academy, I kinda let my suspension of disbelief carry me. Much later, on DS9, when Nog the Ferengi decided to join Starfleet, Cisco had to sponsor him personally, as his ‘race’ or ‘species’ or whatever weren’t members of Starfleet. Seriously, Cisco doesn’t want to, but, after one test where Nog doesn’t steal everything that’s not nailed down, he gets into Starfleet.
It occurred to me then that Data’s situation was somewhat analogous. Its more of a stretch that an android became a full classmate – compared to a Klingon (former enemy) or a Benzyte (they need a trace gas generator mounted under their face to breathe) or a hostile species – like the 1/4 Romulan from the drumhead episode, the Ferengi, but still, it appears all inclusiveness is what Starfleet’s charter is about.
Nitpicks: It’s Sisko, and Benzite.
Data was found by a Starfleet vessel, the USS Trieste I believe, so presumably he impressed someone on board - or one of the Starfleet scientists later studying him - enough to find a sponsor for his admission to the Academy.
I personally find that possibility completely unrealistic which is why I HATE the episode “Measure of a Man” so damn much. He was 2nd officer on a spaceship meaning only 2 people had to die or be incapacitated for him to be in complete command of everyone on the ship - the only master on board. Top dog. It defies all logic that they could let him be in any command position without decisively ruling on exactly what his legal status was. And as evidenced by every prior episode, they decided he was a sentient being entrusted with commanding other beings.
I might have been able to hold my nose and put up with the plot if he had always been exclusively in engineering or science - If they cast it as if the crew talked to him like a human because he was so similar but really he was a walking tool and his legal status never questioned.
But that’s not how it was done, so I hate that episode.
I always assumed that it took Data a while to get into the groove of learning to be human. In other words, his learning was just much slower going before we met him. I also never bought that he was completely without emotions*, and assume he regressed somewhat due to being nervous about being in the real world. He just didn’t know that was why he was doing it. It’s really only the first season or two that he seemed too incompetent to have made it through Starfleet, in my opinion.
*Data acts more like someone who has emotions, but they are bother weaker and repressed heavily because he can’t comprehend them. It’s kinda why I view the emotion chip as such a letdown. Up until it was introduced, it seemed the show was pushing more towards him gradually developing and understanding emotions.