Maria Garate, a 20-year-old transient, was charged on Thursday with attempted murder and assault with a deadly weapon, both with hate crime allegations.
She appeared briefly in a Santa Clara County courtroom with a public defender, but did not enter a plea.
Police say that on Tuesday at about 11 a.m., Garate attacked a 4 year-old sitting in a grocery cart while shopping with her father.
The father jumped to his daughter's rescue, enduring a shot from the crowbar before he and others were able to hold the woman down.
A store employee told us off camera that the suspect yelled that the child deserved it while being arrested.
The family did not know Garate.
Police say the suspect attacked the father and daughter because they are Asian.
People we spoke with at the store were obviously disturbed by what happened.
"The world is just going crazy," said Walmart customer Julio Valdez. "People, they're nervous they're kind of crazy. But especially in this area. We need some help in this area."
"If you've got little kids and stuff stay close to your parents and just watch your kids because you don't know when something's going to jump off or something's going to happen," said Walmart customer John Arechiga.
I talked with a Walmart spokesperson over the phone. She said, "Our thoughts and prayers are with the family. We appreciate the police's quick response and continue to work with them in this investigation."
The spokesperson also says security has been increased at the store in the past year and that Walmart is working with local law enforcement in their investigation.
Police were given surveillance video from the store and are saying the father likely saved his child's life.
"This is any parent's worst nightmare," said Lt. Jason Dwyer. "The father sees it happening right in front of him. Does what any father would do -- jumps in and tries to stop it. He's struck but is able to ultimately stop the attack."
The girl was taken to the hospital with non-life threatening injuries.
Garate is being held without bail. If convicted, Garate could spend the rest of her life in prison.
(The Associated Press contributed to this report)