{"id":544,"date":"2015-01-07T17:47:32","date_gmt":"2015-01-08T02:47:32","guid":{"rendered":"http:\/\/blog.box.kr\/?p=544"},"modified":"2015-01-07T17:47:32","modified_gmt":"2015-01-08T02:47:32","slug":"%ed%95%98%ec%9d%b4%eb%b2%84%eb%84%a4%ec%9d%b4%ed%8a%b8-%ec%82%ac%ec%9a%a9%ec%8b%9c%ec%97%90-%ec%98%a4%eb%9d%bc%ed%81%b4%ec%97%90%ec%84%9c-%eb%82%a0%ec%a7%9c-%ed%98%95%ec%8b%9d%ec%9c%bc%eb%a1%9c","status":"publish","type":"post","link":"https:\/\/blog.box.kr\/?p=544","title":{"rendered":"\ud558\uc774\ubc84\ub124\uc774\ud2b8 \uc0ac\uc6a9\uc2dc\uc5d0 \uc624\ub77c\ud074\uc5d0\uc11c \ub0a0\uc9dc \ud615\uc2dd\uc73c\ub85c \uc870\ud68c\uc2dc\uc5d0 Index \uc548"},"content":{"rendered":"

\ud558\uc774\ubc84\ub124\uc774\ud2b8 \uc0ac\uc6a9\uc2dc\uc5d0 \uc624\ub77c\ud074\uc5d0\uc11c \ub0a0\uc9dc \ud615\uc2dd\uc73c\ub85c \uc870\ud68c\uc2dc\uc5d0 Index \uc548\ud0c0\ub294 \ubb38\uc81c\uac00 \ubc1c\uc0dd..<\/p>\n

 <\/p>\n

\ub0b4\uc6a9\uc744 \uc694\uc57d\ud558\uba74.. \ud558\uc774\ubc84\ub124\uc774\ud2b8\uac00 \ub0a0\uc9dc \ud615\uc2dd\uc73c\ub85c \uc778\uc2dd \ubabb\ud558\uace0 \ud30c\ub77c\ubbf8\ud130 \uae30\uc900\uc73c\ub85c
\n\ubb38\uc790 ( \ud544\ub4dc ) \uc640 \ub0a0\uc9dc ( \ud30c\ub77c\ubbf8\ud130)\ub77c \ud310\ub2e8 \ud558\uace0 \ud544\ub4dc\ub97c \ud568\uc218 \uc4b8\uc5b4\uc11c
\n\ub0a0\uc9dc \ud615\uc2dd\uc73c\ub85c \ubcc0\uacbd \ud568.. \uadf8\ub798\uc11c \uc778\ub371\uc2a4 \ubabb \ud0d0..<\/p>\n

\uacb0\ub860 \uc801\uc73c\ub85c \ud558\uc774\ubc84 \ub124\uc774\ud2b8\ud55c\ub370 \uc774 \ud544\ub4dc\uac00 \ub0a0\uc9dc \ud615\uc2dd\uc774\ub77c\ub294\uac78 \uc778\uc2dd \ud574\uc918\uc57c \ud568.<\/p>\n

\n

What is the problem with Oracle DATE?<\/h2>\n

The problem that was presented in the previous article is dealing with the fact that if a query uses filters on Oracle\u00a0DATE<\/code>\u00a0columns:<\/p>\n

\n
\n
view source<\/a><\/p>\n
\n<\/div>\n

print<\/a>?<\/a>\n<\/div>\n<\/div>\n

\n
1.<\/code>\/\/ execute_at is of type DATE and there's an index<\/code><\/span><\/span>\n<\/div>\n
2.<\/code>PreparedStatement stmt = connection.prepareStatement(<\/code><\/span><\/span>\n<\/div>\n
3.<\/code>\"SELECT * \"<\/code> +<\/code><\/span><\/span>\n<\/div>\n
4.<\/code>\"FROM rentals \"<\/code> +<\/code><\/span><\/span>\n<\/div>\n
5.<\/code>\"WHERE rental_date > ? AND rental_date < ?\"<\/code>);<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n

\u2026 and we\u2019re using\u00a0java.sql.Timestamp<\/code>\u00a0for our bind values:<\/p>\n

\n
\n
view source<\/a><\/p>\n
\n<\/div>\n

print<\/a>?<\/a>\n<\/div>\n<\/div>\n

\n
1.<\/code>stmt.setTimestamp(<\/code>1<\/code>, start);<\/code><\/span><\/span>\n<\/div>\n
2.<\/code>stmt.setTimestamp(<\/code>2<\/code>, end);<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n

\u2026 then the execution plan will turn very bad with a FULL TABLE SCAN or perhaps an INDEX FULL SCAN, even if we should have gotten a regular INDEX RANGE SCAN.<\/p>\n

-------------------------------------\n| Id  | Operation          | Name   |\n-------------------------------------\n|   0 | SELECT STATEMENT   |        |\n|*  1 |  FILTER            |        |\n|*  2 |   TABLE ACCESS FULL| RENTAL |\n-------------------------------------\n\nPredicate Information (identified by operation id):\n---------------------------------------------------\n\n   1 - filter(:1<=:2)\n   2 - filter((INTERNAL_FUNCTION(\"RENTAL_DATE\")>=:1 AND\n              INTERNAL_FUNCTION(\"RENTAL_DATE\")<=:2))\n<\/pre>\n
This is because the database column is widened from Oracle\u00a0DATE<\/code>\u00a0to OracleTIMESTAMP<\/code>\u00a0via this\u00a0INTERNAL_FUNCTION()<\/code><\/em>, rather than truncating thejava.sql.Timestamp<\/code>\u00a0value to Oracle\u00a0DATE<\/code>.<\/p>\n
More details about the problem itself can be seen in the previous article<\/a><\/p>\n
Preventing this INTERNAL_FUNCTION() with Hibernate<\/h2>\n
You\u00a0can<\/em>\u00a0fix this with Hibernate\u2019s proprietary API, using aorg.hibernate.usertype.UserType<\/code><\/a>.<\/p>\n
Assuming that we have the following entity:<\/p>\n
\n
\n
view source<\/a><\/p>\n
\n<\/div>\n
print<\/a>?<\/a>\n<\/div>\n<\/div>\n
\n
01.<\/code>@Entity<\/code><\/span><\/span>\n<\/div>\n
02.<\/code>public<\/code> class<\/code> Rental {<\/code><\/span><\/span>\n<\/div>\n
03.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
04.<\/code>@Id<\/code><\/span><\/span>\n<\/div>\n
05.<\/code>@Column<\/code>(name = <\/code>\"rental_id\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
06.<\/code>public<\/code> Long rentalId;<\/code><\/span><\/span>\n<\/div>\n
07.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
08.<\/code>@Column<\/code>(name = <\/code>\"rental_date\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
09.<\/code>public<\/code> Timestamp rentalDate;<\/code><\/span><\/span>\n<\/div>\n
10.<\/code>}<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n
And now, let\u2019s run this query here (I\u2019m using Hibernate API, not JPA, for the example):<\/p>\n
\n
\n
view source<\/a><\/p>\n
\n<\/div>\n
print<\/a>?<\/a>\n<\/div>\n<\/div>\n
\n
1.<\/code>List<Rental> rentals =<\/code><\/span><\/span>\n<\/div>\n
2.<\/code>session.createQuery(<\/code>\"from Rental r where r.rentalDate between :from and :to\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
3.<\/code>.setParameter(<\/code>\"from\"<\/code>, Timestamp.valueOf(<\/code>\"2000-01-01 00:00:00.0\"<\/code>))<\/code><\/span><\/span>\n<\/div>\n
4.<\/code>.setParameter(<\/code>\"to\"<\/code>, Timestamp.valueOf(<\/code>\"2000-10-01 00:00:00.0\"<\/code>))<\/code><\/span><\/span>\n<\/div>\n
5.<\/code>.list();<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n
The execution plan that we\u2019re now getting is again inefficient:<\/p>\n
-------------------------------------\n| Id  | Operation          | Name   |\n-------------------------------------\n|   0 | SELECT STATEMENT   |        |\n|*  1 |  FILTER            |        |\n|*  2 |   TABLE ACCESS FULL| RENTAL |\n-------------------------------------\n\nPredicate Information (identified by operation id):\n---------------------------------------------------\n\n   1 - filter(:1<=:2)\n   2 - filter((INTERNAL_FUNCTION(\"RENTAL0_\".\"RENTAL_DATE\")>=:1 AND\n              INTERNAL_FUNCTION(\"RENTAL0_\".\"RENTAL_DATE\")<=:2))\n<\/pre>\n
The solution is to add this\u00a0@Type<\/code>\u00a0annotation to all relevant columns\u2026<\/p>\n
\n
\n
view source<\/a><\/p>\n
\n<\/div>\n
print<\/a>?<\/a>\n<\/div>\n<\/div>\n
\n
01.<\/code>@Entity<\/code><\/span><\/span>\n<\/div>\n
02.<\/code>@TypeDefs<\/code>(<\/code><\/span><\/span>\n<\/div>\n
03.<\/code>value = <\/code>@TypeDef<\/code>(<\/code><\/span><\/span>\n<\/div>\n
04.<\/code>name = <\/code>\"oracle_date\"<\/code>,<\/code><\/span><\/span>\n<\/div>\n
05.<\/code>typeClass = OracleDate.<\/code>class<\/code><\/span><\/span>\n<\/div>\n
06.<\/code>)<\/code><\/span><\/span>\n<\/div>\n
07.<\/code>)<\/code><\/span><\/span>\n<\/div>\n
08.<\/code>public<\/code> class<\/code> Rental {<\/code><\/span><\/span>\n<\/div>\n
09.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
10.<\/code>@Id<\/code><\/span><\/span>\n<\/div>\n
11.<\/code>@Column<\/code>(name = <\/code>\"rental_id\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
12.<\/code>public<\/code> Long rentalId;<\/code><\/span><\/span>\n<\/div>\n
13.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
14.<\/code>@Column<\/code>(name = <\/code>\"rental_date\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
15.<\/code>@Type<\/code>(type = <\/code>\"oracle_date\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
16.<\/code>public<\/code> Timestamp rentalDate;<\/code><\/span><\/span>\n<\/div>\n
17.<\/code>}<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n
and register the following, simplified\u00a0UserType<\/code>:<\/p>\n
\n
\n
view source<\/a><\/p>\n
\n<\/div>\n
print<\/a>?<\/a>\n<\/div>\n<\/div>\n
\n
01.<\/code>import<\/code> java.io.Serializable;<\/code><\/span><\/span>\n<\/div>\n
02.<\/code>import<\/code> java.sql.PreparedStatement;<\/code><\/span><\/span>\n<\/div>\n
03.<\/code>import<\/code> java.sql.ResultSet;<\/code><\/span><\/span>\n<\/div>\n
04.<\/code>import<\/code> java.sql.SQLException;<\/code><\/span><\/span>\n<\/div>\n
05.<\/code>import<\/code> java.sql.Timestamp;<\/code><\/span><\/span>\n<\/div>\n
06.<\/code>import<\/code> java.sql.Types;<\/code><\/span><\/span>\n<\/div>\n
07.<\/code>import<\/code> java.util.Objects;<\/code><\/span><\/span>\n<\/div>\n
08.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
09.<\/code>import<\/code> oracle.sql.DATE;<\/code><\/span><\/span>\n<\/div>\n
10.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
11.<\/code>import<\/code> org.hibernate.engine.spi.SessionImplementor;<\/code><\/span><\/span>\n<\/div>\n
12.<\/code>import<\/code> org.hibernate.usertype.UserType;<\/code><\/span><\/span>\n<\/div>\n
13.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
14.<\/code>public<\/code> class<\/code> OracleDate <\/code>implements<\/code> UserType {<\/code><\/span><\/span>\n<\/div>\n
15.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
16.<\/code>@Override<\/code><\/span><\/span>\n<\/div>\n
17.<\/code>public<\/code> int<\/code>[] sqlTypes() {<\/code><\/span><\/span>\n<\/div>\n
18.<\/code>return<\/code> new<\/code> int<\/code>[] { Types.TIMESTAMP };<\/code><\/span><\/span>\n<\/div>\n
19.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
20.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
21.<\/code>@Override<\/code><\/span><\/span>\n<\/div>\n
22.<\/code>public<\/code> Class<?> returnedClass() {<\/code><\/span><\/span>\n<\/div>\n
23.<\/code>return<\/code> Timestamp.<\/code>class<\/code>;<\/code><\/span><\/span>\n<\/div>\n
24.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
25.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
26.<\/code>@Override<\/code><\/span><\/span>\n<\/div>\n
27.<\/code>public<\/code> Object nullSafeGet(<\/code><\/span><\/span>\n<\/div>\n
28.<\/code>ResultSet rs,<\/code><\/span><\/span>\n<\/div>\n
29.<\/code>String[] names,<\/code><\/span><\/span>\n<\/div>\n
30.<\/code>SessionImplementor session,<\/code><\/span><\/span>\n<\/div>\n
31.<\/code>Object owner<\/code><\/span><\/span>\n<\/div>\n
32.<\/code>)<\/code><\/span><\/span>\n<\/div>\n
33.<\/code>throws<\/code> SQLException {<\/code><\/span><\/span>\n<\/div>\n
34.<\/code>return<\/code> rs.getTimestamp(names[<\/code>0<\/code>]);<\/code><\/span><\/span>\n<\/div>\n
35.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
36.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
37.<\/code>@Override<\/code><\/span><\/span>\n<\/div>\n
38.<\/code>public<\/code> void<\/code> nullSafeSet(<\/code><\/span><\/span>\n<\/div>\n
39.<\/code>PreparedStatement st,<\/code><\/span><\/span>\n<\/div>\n
40.<\/code>Object value,<\/code><\/span><\/span>\n<\/div>\n
41.<\/code>int<\/code> index,<\/code><\/span><\/span>\n<\/div>\n
42.<\/code>SessionImplementor session<\/code><\/span><\/span>\n<\/div>\n
43.<\/code>)<\/code><\/span><\/span>\n<\/div>\n
44.<\/code>throws<\/code> SQLException {<\/code><\/span><\/span>\n<\/div>\n
45.<\/code>\/\/ The magic is here: oracle.sql.DATE!<\/code><\/span><\/span>\n<\/div>\n
46.<\/code>st.setObject(index, <\/code>new<\/code> DATE(value));<\/code><\/span><\/span>\n<\/div>\n
47.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
48.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
49.<\/code>\/\/ The other method implementations are omitted<\/code><\/span><\/span>\n<\/div>\n
50.<\/code>}<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n
This will work because using the vendor-specific\u00a0oracle.sql.DATE<\/code>\u00a0type will have the same effect on your execution plan as\u00a0explicitly casting the bind variable in your SQL statement, as shown in the previous article<\/a>:\u00a0CAST(? AS DATE)<\/code>. The execution plan is now the desired one:<\/p>\n
------------------------------------------------------\n| Id  | Operation                    | Name          |\n------------------------------------------------------\n|   0 | SELECT STATEMENT             |               |\n|*  1 |  FILTER                      |               |\n|   2 |   TABLE ACCESS BY INDEX ROWID| RENTAL        |\n|*  3 |    INDEX RANGE SCAN          | IDX_RENTAL_UQ |\n------------------------------------------------------\n\nPredicate Information (identified by operation id):\n---------------------------------------------------\n\n   1 - filter(:1<=:2)\n   3 - access(\"RENTAL0_\".\"RENTAL_DATE\">=:1\n          AND \"RENTAL0_\".\"RENTAL_DATE\"<=:2)\n<\/pre>\n
If you want to reproduce this issue, just query any Oracle\u00a0DATE<\/code>\u00a0column with ajava.sql.Timestamp<\/code>\u00a0bind value through JPA \/ Hibernate,\u00a0and get the execution plan as indicated here<\/a>.<\/p>\n
Don\u2019t forget to flush shared pools and buffer caches to enforce the calculation of new plans between executions, because the generated SQL is the same each time.<\/p>\n
Can I do it with JPA 2.1?<\/h2>\n
At first sight, it looks like the new converter feature in JPA 2.1 (which works just like jOOQ\u2019s converter feature<\/a>) should be able to do the trick. We should be able to write:<\/p>\n
\n
\n
view source<\/a><\/p>\n
\n<\/div>\n
print<\/a>?<\/a>\n<\/div>\n<\/div>\n
\n
01.<\/code>import<\/code> java.sql.Timestamp;<\/code><\/span><\/span>\n<\/div>\n
02.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
03.<\/code>import<\/code> javax.persistence.AttributeConverter;<\/code><\/span><\/span>\n<\/div>\n
04.<\/code>import<\/code> javax.persistence.Converter;<\/code><\/span><\/span>\n<\/div>\n
05.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
06.<\/code>import<\/code> oracle.sql.DATE;<\/code><\/span><\/span>\n<\/div>\n
07.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
08.<\/code>@Converter<\/code><\/span><\/span>\n<\/div>\n
09.<\/code>public<\/code> class<\/code> OracleDateConverter<\/code><\/span><\/span>\n<\/div>\n
10.<\/code>implements<\/code> AttributeConverter<Timestamp, DATE>{<\/code><\/span><\/span>\n<\/div>\n
11.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
12.<\/code>@Override<\/code><\/span><\/span>\n<\/div>\n
13.<\/code>public<\/code> DATE convertToDatabaseColumn(Timestamp attribute) {<\/code><\/span><\/span>\n<\/div>\n
14.<\/code>return<\/code> attribute == <\/code>null<\/code> ? <\/code>null<\/code> : <\/code>new<\/code> DATE(attribute);<\/code><\/span><\/span>\n<\/div>\n
15.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
16.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
17.<\/code>@Override<\/code><\/span><\/span>\n<\/div>\n
18.<\/code>public<\/code> Timestamp convertToEntityAttribute(DATE dbData) {<\/code><\/span><\/span>\n<\/div>\n
19.<\/code>return<\/code> dbData == <\/code>null<\/code> ? <\/code>null<\/code> : dbData.timestampValue();<\/code><\/span><\/span>\n<\/div>\n
20.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
21.<\/code>}<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n
This converter can then be used with our entity:<\/p>\n
\n
\n
view source<\/a><\/p>\n
\n<\/div>\n
print<\/a>?<\/a>\n<\/div>\n<\/div>\n
\n
01.<\/code>import<\/code> java.sql.Timestamp;<\/code><\/span><\/span>\n<\/div>\n
02.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
03.<\/code>import<\/code> javax.persistence.Column;<\/code><\/span><\/span>\n<\/div>\n
04.<\/code>import<\/code> javax.persistence.Convert;<\/code><\/span><\/span>\n<\/div>\n
05.<\/code>import<\/code> javax.persistence.Entity;<\/code><\/span><\/span>\n<\/div>\n
06.<\/code>import<\/code> javax.persistence.Id;<\/code><\/span><\/span>\n<\/div>\n
07.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
08.<\/code>@Entity<\/code><\/span><\/span>\n<\/div>\n
09.<\/code>public<\/code> class<\/code> Rental {<\/code><\/span><\/span>\n<\/div>\n
10.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
11.<\/code>@Id<\/code><\/span><\/span>\n<\/div>\n
12.<\/code>@Column<\/code>(name = <\/code>\"rental_id\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
13.<\/code>public<\/code> Long rentalId;<\/code><\/span><\/span>\n<\/div>\n
14.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
15.<\/code>@Column<\/code>(name = <\/code>\"rental_date\"<\/code>)<\/code><\/span><\/span>\n<\/div>\n
16.<\/code>@Convert<\/code>(converter = OracleDateConverter.<\/code>class<\/code>)<\/code><\/span><\/span>\n<\/div>\n
17.<\/code>public<\/code> Timestamp rentalDate;<\/code><\/span><\/span>\n<\/div>\n
18.<\/code>}<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n
But unfortunately, this doesn\u2019t work out of the box as Hibernate 4.3.7 will think that you\u2019re about to bind a variable of type\u00a0VARBINARY<\/code>:<\/p>\n
\n
\n
view source<\/a><\/p>\n
\n<\/div>\n
print<\/a>?<\/a>\n<\/div>\n<\/div>\n
\n
01.<\/code>\/\/ From org.hibernate.type.descriptor.sql.SqlTypeDescriptorRegistry<\/code><\/span><\/span>\n<\/div>\n
02.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
03.<\/code>public<\/code> <X> ValueBinder<X> getBinder(JavaTypeDescriptor<X> javaTypeDescriptor) {<\/code><\/span><\/span>\n<\/div>\n
04.<\/code>if<\/code> ( Serializable.<\/code>class<\/code>.isAssignableFrom( javaTypeDescriptor.getJavaTypeClass() ) ) {<\/code><\/span><\/span>\n<\/div>\n
05.<\/code>return<\/code> VarbinaryTypeDescriptor.INSTANCE.getBinder( javaTypeDescriptor );<\/code><\/span><\/span>\n<\/div>\n
06.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
07.<\/code>\u00a0<\/span><\/span>\n<\/div>\n
08.<\/code>return<\/code> new<\/code> BasicBinder<X>( javaTypeDescriptor, <\/code>this<\/code> ) {<\/code><\/span><\/span>\n<\/div>\n
09.<\/code>@Override<\/code><\/span><\/span>\n<\/div>\n
10.<\/code>protected<\/code> void<\/code> doBind(PreparedStatement st, X value, <\/code>int<\/code> index, WrapperOptions options)<\/code><\/span><\/span>\n<\/div>\n
11.<\/code>throws<\/code> SQLException {<\/code><\/span><\/span>\n<\/div>\n
12.<\/code>st.setObject( index, value, jdbcTypeCode );<\/code><\/span><\/span>\n<\/div>\n
13.<\/code>}<\/code><\/span><\/span>\n<\/div>\n
14.<\/code>};<\/code><\/span><\/span>\n<\/div>\n
15.<\/code>}<\/code><\/span><\/span>\n<\/div>\n<\/div>\n<\/div>\n
Of course, we can probably somehow tweak thisSqlTypeDescriptorRegistry<\/code>\u00a0to create our own \u201cbinder\u201d, but then we\u2019re back to Hibernate-specific API. The fact is that the JPA 2.1 converter API is not going to be sufficient for these use-cases, as it doesn\u2019t allow you to specify how to interact with JDBC, which is often required.<\/p>\n
Conclusion<\/h2>\n
Abstractions are leaky on all levels, even if they are deemed a \u201cstandard\u201d by the JCP. Standards are often a means of justifying an industry de-facto standard in hindsight (with some politics involved, of course). Let\u2019s not forget that Hibernate didn\u2019t start as a standard and massively revolutionised the way the standard-ish J2EE folks tended to think about persistence, 14 years ago.<\/p>\n
In this case we have:<\/p>\n