Brevet Sergeant Doig was killed and Sergeant Michael Hutchinson wounded after they were allegedly shot by Jaydn Stimson, 26, at a rural property in Senior, near the Victorian border, on November 16.
Stimson remains in hospital under police guard and has been charged with murder and attempted murder.
The police investigation is ongoing.
Acting police commissioner Linda Williams on Monday remembered Sgt Doig as a police officer who had an unwavering dedication to his community and a kind and empathetic nature.
"What I've learned is that Jason was regarded by many as the quintessential bloke who embodies what it means to be a country police officer," Ms Williams told mourners.
"The universal description of Jason is that he was kind, caring, generous and unique."
A police chaplain said Sgt Doig was remembered as a legendary country cop.
SA Premier Peter Malinauskas, ahead of the memorial, announced the state government would donate $100,000 to Women's Safety Services SA in Sgt Doig's honour.
The police officer's family requested mourners also donate to the organisation in lieu of flowers.
Monday's event was the second public memorial in as many weeks, after more than 1000 people gathered to mourn the loss of SA Police Commissioner Grant Stevens' son on Thursday.
Charlie Stevens died on November 18 after sustaining irreversible brain injuries in an alleged hit-and-run incident at schoolies.
Landmarks were lit up in blue in memory of Sgt Doig and in support of the police family more broadly last week.
Blue lights also shone on buildings across Adelaide, including police headquarters, Adelaide Oval, parliament house and Adelaide town hall.
A Police Funeral to celebrate the life & service of Brevet Sergeant Jason Christopher Doig will be held at 11am on 04/12/23 at the Adelaide Convention Centre.— South Australia Police (@SAPoliceNews) Register- https://t.co/cgrG1A7HgIOr watch the service on our FB page or website. pic.twitter.com/qNmUfLnTuNNovember 28, 2023
Ms Williams previously said both Sgt Hutchinson and Constable Rebekah Cass, who was also at the scene of the shooting but was uninjured, were home recovering from the incident.
"(They) placed themselves at great personal risk to render first aid to Brevet Sergeant Doig and handcuff the accused under what was an incredibly confronting and distressing incident," Ms Williams said.
"It is now evident to me that Sergeant Hutchinson and Constable Cass performed their duties on the night with courage and bravery."
Sgt Doig's live-streamed funeral service began at 11am at the Adelaide Convention Centre.
The 53-year-old had served in the southeast for more than a decade after taking up a post at Lucindale in 2011.
He joined the force in 1989.