Sometimes lack of confidence in one area reveals oversight cockyness in stronger areas:

Set up a simple login system from Unity engine to php to mysql db, using android device ID as the login id. Set up database column to accept 32 length varchar for MD5 hashed strings, as I knew the method I was getting the android device ID was automatically being hashed that way and more or less was what I wanted anyway.

Spend 2 days wondering why it would insert the logins with 0 issue, but could never retrieve them. Due to lack of web development and PHP skills, I assumed I was screwing up the handling of mysqli_num_rows() (to check whether I was inserting or selecting in the query) or simply screwing up my SQL queries.

Rewrite the code a few times, even went back to a method I had used in the past.

Today it dawned on me that my testing machines deviceID had been getting trimmed to the 32 character limit. Turns out I didn't account for my workstations device ID to be automatically hashed like the android device id is.

For 2 days I was obtaining and sending a 40 character string to a 32 character limit varchar and blaming my lack of PHP skills........

Back to my niche I go!