How do I query a sheet select the columns I want and cocnatenate certain rows in the same query

[Bryan Mcgraw]

I would like to concatenate columns d e f after I have selected them from a sheet source and extracted the specific data I want by identifier. How can I do this in the same command string...Here is an example : =QUERY(HRADMIN, "Select a,b,c,d&e&f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,aa,ab,ac,ad,ae,af,ag,ah,ai,ak, where 'bryan' ")  I would like to concatenate column d e and f