count
Returns the number of records with non-NULL values for the specified field. If all records are NULL, the function returns 0.
Syntax
Section titled “Syntax”count( <expr> )Arguments
Section titled “Arguments”<expr>
Section titled “<expr>”A column name, which can be a qualified name (for example, database.schema.table.column_name).
Returns
Section titled “Returns”Returns a value of type int.