John Gill Commentary 2 Samuel 11:17

"And the men of the city went out, and fought with Joab: and there fell some of the people, even of the servants of David; and Uriah the Hittite died also." — 2 Samuel 11:17 (ASV)

And the men of the city went out
Made a sally out, as Joab expected they would, when they appeared before them at that part of the city where valiant men were:

and fought with Joab ;
at least with part of his army posted with Uriah:

and there fell [some] of the people of the servants of David :
which made David's sin the more heinous, that several lives were lost through the stratagem he devised to procure the death of Uriah; who could not be placed in a dangerous post alone, and therefore others must be sacrificed with him, as were:

and Uriah the Hittite died also ;
which was the thing aimed at, and the end to be answered by this scheme.