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BLOBs and CLOBs
Applies to ✅ Open Source Edition ✅ Express Edition ✅ Professional Edition ✅ Enterprise Edition
jOOQ aims for hiding all JDBC details from jOOQ client API. Specifically, java.sql.Clob and java.sql.Blob are quite "harsh" APIs with a few caveats that may even depend on JDBC driver specifics.
Clob and Blob are resources (but not java.lang.AutoCloseable!) with open connections to the database. This makes no sense in an ordinary jOOQ context, when eagerly fetching all the results through fetch() methods. fetchLazy() and fetchStream() might be candidates where Clob and Blob types could make sense as the underlying java.sql.ResultSet and java.sql.PreparedStatement are still open while consuming these resources.
ByteArrayInputStream and ByteArrayOutputStream on the other hand are two different types which cannot be represented as a single Field<T> type. If either would be chosen as the <T> type, we'd get read-only or write-only fields. So for full lazy streaming support, we'd need another 2-way wrapper type, similar to Clob and Blob.
In many cases, streaming binary data isn't really necessary as thebyte[] can be easily kept in memory (and it is done so for further processing anyway, e.g. when working with images), so the extra work might not really be needed. This is particularly true in Oracle, where BLOBs are the only binary types in the absences of a formal (VAR)BINARY type, and CLOBs start at 4000 bytes.
If you want to override jOOQ's default behaviour, use either org.jooq.impl.ClobBinding or org.jooq.impl.BlobBinding, see custom data type bindings as well as using a binding in code generation for more details.
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