implode（）：传入的参数无效

Question

 $fields_arr = "SHOW FIELDS FROM 'payslip' WHERE FIELD NOT IN ('ID','Tax_Number','Employee_Number','Payslip_Number','Salary','Bonus','  Housing_Allowance','House1','Transport_Allowance','Travel_Allowance','Vehicle_Allowance','  Vehicle1','Cellphone_Allowance','   Entertainment_Allowance','  Company_Car','  Medical_Allowance','DSocial_Security',' DHousing_Allowance','DCompany_Car','DContributions','Other_Deductions','DVehicle_Allowance','Other_Allowance','Total_Income','Taxable_Income','Tax_Payable','Overtime','Overtime_Hours','Payday','Pension','Provident_Fund','Retirement_Annuity','Study_Policy','Month','Year','Company')";

$result3 = mysqli_query($conn, $fields_arr);
$fields = implode(',',$result3);

The error comes from the above code as i thing an array is not passed but another form of data type any help on the problem ?error i get is "implode(): Invalid arguments passed "

$dql = "SELECT $fields FROM $tb2_name WHERE Month='$month' AND Year='$year' AND Employee_Number='$user' ";

Answer 1

You must first fetch the data with for example mysqli_fetch_assoc:

$fields_arr = "SHOW FIELDS FROM 'payslip' WHERE FIELD NOT IN ('ID','Tax_Number','Employee_Number','Payslip_Number','Salary','Bonus','  Housing_Allowance','House1','Transport_Allowance','Travel_Allowance','Vehicle_Allowance','  Vehicle1','Cellphone_Allowance','   Entertainment_Allowance','  Company_Car','  Medical_Allowance','DSocial_Security',' DHousing_Allowance','DCompany_Car','DContributions','Other_Deductions','DVehicle_Allowance','Other_Allowance','Total_Income','Taxable_Income','Tax_Payable','Overtime','Overtime_Hours','Payday','Pension','Provident_Fund','Retirement_Annuity','Study_Policy','Month','Year','Company')";

$result3 = mysqli_query($conn, $fields_arr);
$arr = mysqli_fetch_assoc($conn, $result3);
$fields = implode(',',$arr);