Setting PostgreSQL enums using a JDBC ResultSet - postgresql

Question

I'm trying to copy data from a MySQL database to an equivalent PostgreSQL database, doing a load/insert through Java using JDBC. I get this error whenever I try to copy an enum column:
org.postgresql.util.PSQLException: ERROR: column "mycol" is of type mytable_mycol_enum but expression is of type character varying
Hint: You will need to rewrite or cast the expression.
Position: 194
The Java code (simplified and anonymized):
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection mysqlConn = DriverManager.getConnection(
"jdbc:mysql://localhost/mysqldb", "user", "pass");
Class.forName("org.postgresql.Driver").newInstance();
Connection pgConn = DriverManager.getConnection(
"jdbc:postgresql://othercomp/pgdb", "user", "pass");
Statement selStatement = mysqlConn.createStatement();
ResultSet selSet = selStatement.executeQuery("SELECT * FROM mytable");
Statement insStatement = pgConn.createStatement(
ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE);
Resultset insSet = insStatement.executeQuery("SELECT * FROM mytable WHERE 0=1");
insSet.moveToInsertRow();
while(selSet.next())
{
ResultSetMetaData metaData = selSet.getMetaData();
for (int i = 1; i <= metaData.getColumnCount(); i++)
{
String colName = metaData.getColumnName(i);
Object obj = selSet.getObject(colName);
insertSet.updateObject(colName, obj);
}
insertSet.insertRow();
}
This works fine for tables without an enum column, but
In MySQL I have a column mycol of type enum('A','B','C')
In PostgreSQL I have mycol of type mytable_mycol_enum with CREATE TYPE mytable_mycol_enum AS ENUM ('A','B','C')
How do I set the enum value?

Answer 1

You have to cast the value, so that postgresql understands it:
insert into mytable (mycol) values ('A'::mytable_mycol_enum)
You might have to use a named insert statement, not the generic one in your example. Also, try it in psql first to see if it works.
HTH