Empty filters are being used in SQL statement

Just recently installed dev version to correct php error message. But now the filters are not working properly. When filters are empty, they are being generated in the SQL command as = (''). This causes no results to be returned.
Here is the SQL from the dev version
WHERE (node.type in ('registration'))
AND (UPPER(node_data_field_reg_no.field_reg_no_value) = UPPER('03-160'))
AND (UPPER(node_data_field_reg_no.field_pi_last_value) = UPPER(''))
AND (UPPER(node_data_field_reg_no.field_cont_level_value) = UPPER(''))
AND ((node_data_field_reg_no.field_status_value) = (''))
AND ((node_data_field_reg_no.field_inst_abr_value) = (''))
ORDER BY node_data_field_reg_no_field_reg_no_value ASC

Here is the SQL from alpha3 version:
WHERE (node.type in ('registration'))
AND ((node_data_field_reg_no.field_reg_no_value) = ('03-160'))
ORDER BY node_data_field_reg_no_field_reg_no_value ASC