Re: [PATCH] Empty arrays cause SQLExceptions when using Array.getArray

This has been saved for the 7.3 release:

    http://candle.pha.pa.us/cgi-bin/pgpatches2

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Doug Fields wrote:
> I have fixed a minor bug in empty arrays as described below - Unified
> Context Diff provided at the end:
>
> I have the following table and values:
>
> =# \d array_test
>                                Table "array_test"
>   Attribute
> |   Type    |                       Modifier
> -----------+-----------+-------------------------------------------------------
>   id        | integer   | not null default nextval('"array_test_id_seq"'::text)
>   first     | integer[] |
>   second    | integer[] |
>   number    | integer   |
> Index: array_test_pkey
>
> =# select * from array_test;
>   id |   first    |              second               | number
> ----+------------+-----------------------------------+--------
>    1 | {1,2,3}    | {4,5,6}                           |      7
>    2 | {10,20,30} | {40,50,60}                        |     70
>    3 | {100,200}  | {300,400,500,600}                 |    700
>    4 | {1000}     | {2000,3000,4000,5000,6000}        |   7000
>    5 | {}         | {10000,2000,3000,4000,5000,6000}  |  70000
>    6 |            | {100000,2000,3000,4000,5000,6000} | 700000
>    7 | {9,8,7}    | {6,5,4}                           |   8482
> (7 rows)
>
> When I am getting row 5, the ResultSet.getArray().getArray() call fails:
>
> DbArrayTest.doTest: SQLException: Bad Integer
> DbArrayTest.doTest: SQLState:     null
> DbArrayTest.doTest: VendorError:  0
> Bad Integer
>          at org.postgresql.jdbc2.ResultSet.toInt(ResultSet.java:1481)
>          at org.postgresql.jdbc2.Array.getArray(Array.java:127)
>          at org.postgresql.jdbc2.Array.getArray(Array.java:54)
>          at com.pexicom.test.DbArrayTest.doTest(DbArrayTest.java:55)
>
> Code snippet in question:
>
>          Array arrayObj;
>          int[] array;
>              while (rs.next()) {
>                  System.out.println("\nColumn 1: " + rs.getInt(1));
>                  arrayObj = rs.getArray(2);
>                  if (arrayObj != null) {
>                      array = (int[])arrayObj.getArray();
>                      System.out.println("Column 2: " + arrayObj);
>
> It fails at the arrayObj.getArray() call.
>
> This shouldn't happen; it should return a zero-length array.
>
> The diffs for my fix against the 7.2 source code:
>
> diff -ru5 org-orig/postgresql/jdbc2/Array.java org/postgresql/jdbc2/Array.java
> --- org-orig/postgresql/jdbc2/Array.java        Mon Nov 19 18:16:46 2001
> +++ org/postgresql/jdbc2/Array.java     Wed Feb 20 19:50:41 2002
> @@ -72,11 +72,15 @@
>                  if (index < 1)
>                          throw new PSQLException("postgresql.arr.range");
>                  Object retVal = null;
>
>                  ArrayList array = new ArrayList();
> -               if ( rawString != null )
> +               /* Check if the String is also not an empty array
> +                * otherwise there will be an exception thrown below
> +                * in the ResultSet.toX with an empty string.
> +                * -- Doug Fields <dfields-pg-jdbc@pexicom.com> Feb 20, 2002 */
> +               if ( rawString != null && !rawString.equals("{}") )
>                  {
>                          char[] chars = rawString.toCharArray();
>                          StringBuffer sbuf = new StringBuffer();
>                          boolean foundOpen = false;
>                          boolean insideString = false;
>
>
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