Re: [GENERAL] Fwd: Query parameter types not recognized - Mailing list pgsql-general

On 02/10/2017 01:51 PM, Roberto Balarezo wrote:

Hi,

The parameter defaultDueDate is a java.sql.Date object, an actual Date.
When I run the query with the value in it, it works:
```sql
db=> select COALESCE(duedate, date '2017-02-01' + 1) from invoices order
by duedate desc;
      coalesce
---------------------
 2017-02-02 00:00:00
 2017-02-02 00:00:00
 2016-11-14 00:00:00
 2017-02-10 00:00:00
 2017-02-02 00:00:00
 2017-02-13 00:00:00
 2017-02-02 00:00:00
 2017-02-02 00:00:00
```

But when I send it as a parameter, it ignores it and seems to think the
expression is of type interger.

Which would indicate to me that is what is being passed in the parameter. If I would guess, from information here:

https://docs.oracle.com/javase/7/docs/api/java/sql/Date.html

milliseconds since January 1, 1970 00:00:00.000 GMT.

Turn on/up logging in Postgres and run a query with that java.sql.Date object. I am betting that what you will see in the logs is an integer.

2017-02-10 16:32 GMT-05:00 Adrian Klaver <adrian.klaver@aklaver.com
<mailto:adrian.klaver@aklaver.com>>:

    On 02/10/2017 07:17 AM, Roberto Balarezo wrote:

        Hi, I would like to know why this is happening and some advice
        if there
        is a way to solve this problem:

        I have a query like this:

        |select COALESCE(duedate, ? + 1) from invoices order by duedate desc
        limit 10; |


    What is the 1 in ? + 1 supposed to represent?


        where ? is a query parameter. I’m using JDBC to connect to the
        database,
        and sending parameters like this:

        |query.setDate(1, defaultDueDate); |

        Where defaultDueDate is a java.sql.Date object. However, when I
        try to
        execute the query, I get this error:

        |org.postgresql.util.PSQLException: ERROR: COALESCE types timestamp
        without time zone and integer cannot be matched |


    So what is the actual value of defaultDueDate?

    Looks like it is an integer from the ERROR message.

    Might want to look in the Postgres logs to see if they show anything
    that might help.


        Why is it inferring that the type is integer, when I send it as
        Date??


    I don't use Java, but I did find the below, don't know if it helps?:

    https://jdbc.postgresql.org/documentation/94/escapes-datetime.html
    <https://jdbc.postgresql.org/documentation/94/escapes-datetime.html>



        When I force the type using a cast, like this:

        |select COALESCE(duedate, CAST(? AS DATE) + 1) from invoices
        order by
        duedate desc limit 10; |

        I get this error:

        |org.postgresql.util.PSQLException: ERROR: could not determine
        data type
        of parameter $1 |

        If I’m telling PostgreSQL that the parameter is going to be a
        Date, and
        send through the driver a Date, why it is having trouble
        determining the
        datatype of the parameter??
        What can I do to make it work?

        For reference, I’m using PostgreSQL 9.2.15 and JDBC driver
        9.4.1207.jre6.

        Thanks for your advice!

        ​



    --
    Adrian Klaver

    adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>

--
Adrian Klaver
adrian.klaver@aklaver.com