Character varying = bytea in PostgreSQL

Java is used to develop PostgreSQL database compatibility applications, which is different from Oracle:

Oracle JDBC driverProgramThe Java string type can be properly mapped to the numberic (integer) of the database, while the Postgres will fail.

In addition, when Hibernate is used, the frequent ignore handler: operator does not exist: character varying = bytea problem. Do not be misled by this description, it is not a comparison of character varying = bytea type in SQL statements, but when Hibernate is used to bind parameters and the parameter value is null, the hibernate or PostgreSQL driver maps this parameter to the varbinary type. PostgreSQL considers varbinary as the bytea type: