Dear all,
I maybe found a problem with the "isCaseSensitive" method in the
"ResultSetMetadata" class when using it on a "AS" clause.
With the following test DB:
> test=> CREATE TABLE "Student" ("ID" INTEGER,"Name" VARCHAR(15));
> CREATE TABLE
> test=> INSERT INTO "Student" ("ID", "Name") VALUES(10,'Venus');
> INSERT 0 1
I execute the query with the "AS" clause:
> test=> Select ('Student' || "ID" ) AS StudentId, "ID", "Name" from
> "Student" ;
> studentid | ID | Name
> -----------+----+-------
> Student10 | 10 | Venus
> (1 ligne)
The StudentId regular identifier becomes studentid, but this kind of
transformation is not a problem, since a regular identifier is not case
sensitive.
The problem is where I execute my query in JDBC:
> @Test
> public void testAsCaseSensitive() throws Exception {
> Connection conn =
> DriverManager.getConnection("jdbc:postgresql://127.0.0.1:5432/test","root","root");
> java.sql.Statement s = conn.createStatement(
> ResultSet.HOLD_CURSORS_OVER_COMMIT, ResultSet.CONCUR_READ_ONLY);
> s.executeQuery("Select ('Student' || \"ID\" ) AS StudentId from
> \"Student\";");
> ResultSet rs = s.getResultSet();
> ResultSetMetaData metaData = rs.getMetaData();
> int n = metaData.getColumnCount();
> for (int i = 1; i <= n; i++) {
> System.out.println("Column: "+metaData.getColumnLabel(i)+"
> "+metaData.isCaseSensitive(i));
> }
> }
I obtain the output:
> Column: studentid true
Then, the column name is changed from StudentId to studentid, but the
"isCaseSensitive" flag is "true". I think it is not correct, since it is
impossible from now, when a user ask for the StudentId column to
retrieve it from a resultset. The "isCaseSensitive" don't authorize to
accept the string StudentId as a valid column name for the studentid
column in the ResultSet.
This on: psql (PostgreSQL) 9.1.4 (debian-squeeze backport packages),
with Maven dependency on JDBC plugin:
> <dependency>
> <groupId>postgresql</groupId>
> <artifactId>postgresql</artifactId>
> <version>9.1-901.jdbc4</version>
> </dependency>
I hope that I don't have miss something and I don't bother you....
Best regards,
Laurent Mazuel
--
Laurent Mazuel (lmazuel@antidot.net)
Ingénieur R&D, Web Sémantique
Antidot - Solutions de recherche d'information
29 avenue Jean Monnet, 13410 LAMBESC (FRANCE)
Tel: (33) 4 42 63 67 90 / Fax: (33) 4 42 28 61 03
