Re: Possible bug related to primary keys autogeneration

as the comments around

https://github.com/pgjdbc/pgjdbc/blob/7311b4ef160231780323573911c1543d0515340b/pgjdbc/src/main/java/org/postgresql/jdbc/PgStatement.java#L1205

suggest if escape is turned on we will quote the returning. The reason for
this is to allow people who really want ID returned as opposed to id.

this is unlikely to be changed.

Dave Cramer

davec(at)postgresintl(dot)com
www.postgresintl.com

On 15 July 2016 at 10:41, Andrea Bergia <a(dot)bergia(at)list-group(dot)com> wrote:

> Being consistent with cases is generally good advice, but unfortunately my
> code has to run on multiple databases and it's very hard to control cases
> in all the code.
>
> Besides, it seems to me that the behavior is inconsistent. I can use
> whatever case I want in the INSERT INTO clause:
>
> INSERT INTO Documents (name) VALUES ('abc');
> INSERT INTO Documents (NAME) VALUES ('abc');
> INSERT INTO Documents (NaMe) VALUES ('abc');
> but when using the "returning" clause, I have to be careful about my
> identifiers... Besides, if the driver wasn't quoting the RETURNING clause,
> everything would work well (as I have tested using the debugger). So, any
> chance that can be changed in the driver?
>
>
> On 15/07/2016 16:30, Dave Cramer wrote:
>
> This is an artifact of how postgresql treats case.
>
> PostgreSQL folds to lower case. short version "do not use UPPER CASE
> identifiers"
>
> If you are intent on using upper case you have to use new
> String[]{"\"ID\""}) to force upper case (to be honest I'm not even sure
> that would work)
>
> as I said don't use UPPER CASE identifiers
>
> Dave Cramer
>
> davec(at)postgresintl(dot)com
> www.postgresintl.com
>
> On 15 July 2016 at 10:09, Andrea Bergia <a(dot)bergia(at)list-group(dot)com> wrote:
>
>> Hello, I have an issue regarding the retrieval of autogenerated keys
>> using JDBC.
>>
>> I am running both the client and the server on windows; the client using
>> the JDBC driver 9.4.1208 and the server has version "PostgreSQL 9.5.3 on
>> x86_64-pc-mingw64, compiled by gcc.exe (Rev5, Built by MSYS2 project)
>> 4.9.2, 64-bit".
>>
>> I have the following schema:
>>
>> CREATE TABLE Documents (
>> id SERIAL,
>> name VARCHAR(100),
>> CONSTRAINT PK_Documents PRIMARY KEY (id)
>> );
>>
>> and the following Java code:
>>
>> try (Connection connection =
>> DriverManager.getConnection("jdbc:postgresql://localhost/sampledb",
>> "sampledb", "")) {
>> connection.setAutoCommit(false);
>> try (PreparedStatement ps = connection.prepareStatement("INSERT INTO
>> Documents (name) VALUES (?)", new String[]{"ID"})) {
>> ps.setString(1, "DocName");
>> ps.executeUpdate();
>>
>> try (ResultSet generatedKeys = ps.getGeneratedKeys()) {
>> if (!generatedKeys.next()) {
>> throw new RuntimeException("Should have been able to
>> retrieve the generated keys");
>> }
>> int generatedKey = generatedKeys.getInt(1);
>> System.out.println("The generated key is " + generatedKey);
>> }
>> }
>> }
>>
>> I get the following exception:
>> Exception in thread "main" org.postgresql.util.PSQLException: ERROR:
>> column "ID" does not exist
>>
>> Debugging a bit, the issue seems to be in PgConnection.java, line 1641:
>> since "escape" is set to "true", the driver is adding RETURNING "ID",
>> quoting the column name. Since the column name's case is different between
>> the CREATE TABLE statement and the code, PostgreSQL generates an exception.
>> In fact, if I use new String[]{"id"}, the program works.
>>
>> I'm wondering whether this can be classified as a bug, or is intentional.
>> The driver doesn't quote column names generally; it seems to me that this
>> behavior is a bit annoying. However, I have no idea what the implications
>> of removing the escaping would be. I do have a workaround for the moment,
>> but I would like to know whether this is something that can be changed or
>> not.
>>
>> I have uploaded a complete, minimal project which includes the code above
>> at https://github.com/andreabergia/psql-jdbc-possible-bug-report.
>>
>> Thanks for your time, and for your excellent product.
>>
>> --
>> Andrea Bergia
>> List S.p.A.
>>
>>
>>
>> --
>> Sent via pgsql-jdbc mailing list (pgsql-jdbc(at)postgresql(dot)org)
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>>
>
>
> --
> Andrea Bergia
> List S.p.A.
>
>