Dear Devs, I would like to help expand the jdbc resultset metadata available
when querying a table. Consider the following example:
CREATE TABLE ARTICLE (
ID BIGINT,
BODY text,
LAST_MODIFIED TIMESTAMP with time zone,
CONSTRAINT PK_ ARTICLE PRIMARY KEY (ID)
);
After creating the table, I can query the column metadata using the
java.sql.ResultSetMetaData. Example:
java.sql.ResultSet rs = stmt.executeQuery("select * from article);
java.sql.ResultSetMetaData rsmd = rs.getMetaData();
However, the resultset /column metadata will return the following types:
- id: long- body: object- last_modified: object
Note that the body and last_modified fields are identified as generic objects
instead of their formal java types. This is not consistent with other jdbc
drivers (e.g. postgresql, h2, etc).
After a little digging, I found the JdbcColumnMeta(GridQueryFieldMetadata
info) constructor which calls the JdbcThinUtils class. However, at this point
the GridQueryFieldMetadata is already mapped to a generic "object" so it is
impossible to return the correct type from the JdbcThinUtils class.
Next, I decided to see how tables are created in the first place. Specifically,
the GridSqlQueryParser.parseCreateTable() method. In there, I can see the
correct column metadata. For example, if I add the following code in the
parseCreateTable method...
for (Column col : data.columns){
System.out.println(col.getName() + " (" + col.getType() + ")");
}
...it will print the following:
ID (5)
BODY (16)
LAST_MODIFIED (24)
I would like to preserve this metadata so that I can see it when using the jdbc
resultset metadata object. Any suggestions?
Note that the ID column type (5) is preserved. I suspect the other types
identified in the JdbcThinUtils class are preserved as well.
Thanks in advance,Peter
