Insert too-small double produces wrong exception via Postgres

[Tim Blackman]

Using the Postres server to insert a too-small value produces a parse
exception. There is no underflow exception defined, so it is not clear
what exception this should produce.

It is also unclear why this underflow should produce an exception rather
than resulting in truncation.

SQL:

  CREATE TABLE t (double_field double)
  INSERT INTO t VALUES (4.9E-325)

Result:

  org.postgresql.util.PSQLException: ERROR: [] Floating point exponent underflow: INSERT INTO t VALUES (4.9E-325)
 at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2102)
 at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1835)
 at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)
 at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:500)
 at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:374)
 at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:366)
 at com.akiban.sql.pg.YamlTester$StatementCommand.execute(YamlTester.java:436)

To reproduce:

  mvn test -Dtest=PostgresServerMiscYamlIT -Dcom.akiban.sql.pg.PostgresServerMiscYamlIT.CASE_NAME_REGEXP=bug-insert-double-underflow

Reproduced in trunk revision 1239

[Mike McMahon (mmcm)]

See Bug #889297.

[Timothy Wegner (timmwegner)]

This error is specific to literal floats. We should probably have a separate handling of computed floats.