Re: [hibernate-dev] MySQL versus MariaDB

https://hibernate.atlassian.net/browse/HHH-9969 On Wed, Jul 22, 2015 at 2:18 PM Steve Ebersole <steve(a)hibernate.org&gt; wrote: > As I have developed the matrix tests against MariaDB I have had in the > back of my head whether we might want to develop a Dialect for MariaDB. As > I understand it, MariaDB does strive to remain compatible with MySQL but it > does offer some enhancements. And it might have some minor deviations. > Today I think I found one such deviation, in their respective support for > casting decimal/floating-point values. I came across this because of some > failed tests. > > There are quite a few resolved issues in Jira wrt MySQL and casting. So I > have to assume these tests work on MySQL which tells me there is a > deviation in their behavior... > > The tests in question (more or less) do: "select ... cast( x as > big_decimal ) ...". We understand big_decimal as java.sql.Types#NUMERIC > for which the MySQL Dialect says to use "decimal" for casting purposes. > > On MariaDB at least "decimal" (no precision) leads to a data trunction. > We are expecting a value like "12.399999618530273" but get back "12.0". > Because for MariaDB DECIMAL is equivalent to DECIMAL(10,0). > > So as it is, for this minor case at least the MySQL dialects work against > MySQL databases (we assume) but fail against MariaDB databases. > > The other difficulty with a dialect specific for MariaDB is > auto-detection. The MariaDB JDBC drivers report the underlying database as > mysql. > _______________________________________________ hibernate-dev mailing list hibernate-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev