Yes, 9 APs is enough to get into Columbia University. And you are correct, as long as you have all the other preferred attributes in your application, you will be a strong candidate.
There is a big misconception here with CV members and various other sites, that you need 12-15 APs or a majority of the APs offered to get into the Ivy League. There are different ways to show your admissions team that you challenged yourself in high school academically, regardless of the AP count. And keep in mind that during senior year, APs are less important than in 10th and 11th grade because a.) you grades may not be reported if you apply ED/EA/REA and b.) if you apply RD, your half year report only will reflect 50% of your full year's grades and c.) all your admissions decisions will come out before the middle of May when you are supposed to take your AP exams. So if you load up on a 6 APs senior year that's indeed a full plate of course rigor. If you haven't demonstrated in 10th and 11th grade that you can gets As and 5s on your AP exams, over-extending yourself doesn't look as impressive as it sounds because some of the AOs, will regard it as a last ditch attempt to impress them. They may in fact feel the train has already left the AP station and prefer to admit those who had completed most of their APs in 10th and 11th grade.
Other ways to show course rigor:
-If your HS doesn't offer APs, you can always opt to take online college courses either at accredited colleges that offer them or through highly reputable MOOCs like outlier.org, eDx.org
-If your high schools only offers the IB program, that is a perfectly good surrogate for AP course rigor.
-And if you are resourceful and intellectually curious, you can always use your summers and breaks to participate in academic programs, a research gig or internship that teaches you something of value.
-If you attend a Private Day or Boarding School that is prestigious and a feeder in to the Ivy League, then there will be ZERO APs or IBs in the course catalog. Top private schools have their own academic standard for how they teach. At most of these schools, they offer 500 or 600 level classes, sometimes 700 level. These are all college level either freshman or sophom*ore level courses. In theory, you could be a perfect candidate at a boarding school without ever having taken a single AP or IB class.
I was accepted to Columbia with 9 APs. I also had 5 years of math through Calculus & Stats, 6 years of English including Honors 9th/10th, AP Lang, AP Lit, journalism, editor of newspaper, 5 years of French, 4 years of Science, and 4 years of history. Outside of HS, I earned 6 college credits from UPitt, and 24 DE credits from my local CC. I was captain of the girls waterpolo team, 3 yrs student leadership, Chairperson of our School District DEIA board (which is an elected adult position), student board member of our city's parks and recs advisory board, board member of the SITE council, board member of respond to racism, steering committee member of our public library, director of LO for Love another anti-racism community board, scored a 35+ on my ACT, scored 4.5 avg on my 9 AP exams, and was a US Presidential Scholar semi-finalist and wrote for the town newspaper on the side. Columbia was like a 43% CV chancing for me when I applied but now it's more competitive my CV chances are down to 39%.
I'm sharing this to say that in spite of the pandemic I was still able to do all these ECs because they were 100% on zoom calls versus public meetings at city hall or the school auditorium. The most important thing I think to get into an Ivy league schools is that your narrative about being a compassionate human being that wants to make the world a better places has to be believable and evidenced by how you use your time in HS efficiently to make an impact. If you just want a get an excellent education and make money or be the best programmer, then don't apply to an Ivy league school because you can easily get to your goal by applying to 25-50 colleges that specialize in that sort of thing. My dad went to CMU and if he would tell me that it's the best CS school in the country even better than any Ivy league school so I believe him. Other great CS schools are Rice, MIT, GTech, UI, UCLA, UC Berkeley, UT Austin, UWash. And if your goal is to land an investment banking job a GS, MS, or JP Morgan, you can get there by attending Baruch College, UCBerkeley Haas, NYU, UMich, MIT, UTAustin, Rutgers U.,
I hope this answer was helpful to you and any other CV member reading this.
