php插入数据库无法正常工作

I am trying to insert some information into the database but it is not working. The following is my code:

$sql4 = "INSERT INTO favorites (posted-date,posted-time,posted-
datetime,journalid, by)  VALUES ('test','test','test','test','test')";

Try

$sql4 = "INSERT INTO `favorites` (`posted-date`,`posted-time`,`posted-datetime`,`journalid`, `by`) VALUES ('test','test','test','test','test')";

Also check if you are connecting to your database correctly.

And have a look at your table and all the fields if they are of correct type and exists.

It finally worked. I still did not figure out the cause of the error, but the following is the working code:

$sql4 = "INSERT INTO favorites ( id , posted-date , posted-time , posted-datetime , journalid , by ) VALUES ( NULL , 'test', 'test', 'test', 'test', 'test' )";