Syntax error at end of input in PostgreSQL

You are using Go right?

try:

db.Query(`SELECT COUNT(*) as N FROM email WHERE address = $1`, email)

You haven't provided any details about the language/environment, but I'll try a wild guess anyway:

MySQL's prepared statements natively use ? as the parameter placeholder, but PostgreSQL uses $1, $2 etc. Try replacing the ? with $1 and see if it works:

WHERE address = $1

The error messages in PostgreSQL are very cryptic.

In general, I've found that Postgres error messages are better than competing products (ahem, MySQL and especially Oracle), but in this instance you've managed to confuse the parser beyond sanity. :)

In golang for queries we have use

• MySQL uses the ? variant
• PostgreSQL uses an enumerated $1, $2, etc bindvar syntax
• SQLite accepts both ? and $1 syntax
• Oracle uses a :name syntax

In my case, it was due to using a -- line comment where the program that was responsible for interacting with the database read in the multiple lines of my query all as one giant line. This meant that the line comment corrupted the remainder of the query. The fix was to use a /* block comment */ instead.