define a sequelize like below:

 

var Program=sequelize.define('Program',{

programCode:{

type:Sequelize.STRING,

primaryKey:true

},

programName:Sequelize.STRING,

},

module.exports.addProgram=function(programData){

return new Promise((resolve,reject)=>{

for ( var i in programData){

if(programData[i]=="")

programData[i]=null;

};

Program.create({

programCode:programData.programCode,

programName:programData.programName,

}) .then((data) => {

console.log("data:", data)

resolve(data);}

)

.catch((err) => {

reject ("Unable to Add the program");

return;

});

});

}

I know the programCode primaryKey should not be null, but if I input null in programCode, I will get some error. How could I handle this error?