Question

Let’s say I want to avoid using bind variables in JDBC and run SQL using “ad-hoc” statements, e.g:

connection.createStatement().executeQuery("SELECT ...");

Is there any convention / JDBC escape syntax to inline BLOB data types? I know that H2 has this syntax:

INSERT INTO lob_table VALUES (X'01FF');

But that’s not a standard. Any general solutions? Note, I’m interested in a general approach. I know that this can turn out to be terribly inefficient.

Answer 1

There probably isn’t a JDBC escape syntax, so I searched around a bit and found and successfully tested the following:

• SQL Server, Sybase ASE, Sybase SQL Anywhere

  INSERT INTO lob_table VALUES (0x01FF);
  

• DB2

  -- Use a blob constructor. This is not needed for VARCHAR FOR BIT DATA types
  INSERT INTO lob_table VALUES (blob(X'01FF'));
  

• Derby, H2, HSQLDB, Ingres, MySQL, SQLite

  INSERT INTO lob_table VALUES (X'01FF');
  

• Oracle

  -- As mentioned by a_horse_with_no_name, keep in mind the relatively low
  -- limitation of Oracle's VARCHAR types to hold only 4000 bytes!
  INSERT INTO lob_table VALUES (hextoraw('01FF'));
  

• Postgres

  -- There is also hex encoding as of Postgres 9.0
  -- The explicit cast is important, though
  INSERT INTO lob_table VALUES (E'\\001\\377'::bytea);
  

  See A.H.’s answer for more details about Postgres’ hex encoding

• SQL Standard

  -- SQL actually defines binary literals as such 
  -- (as implemented by DB2, Derby, H2, HSQLDB, Ingres, MySQL, SQLite):
  <binary string literal> ::=
    X <quote> [ <space>... ] 
    [ { <hexit> [ <space>... ] <hexit> [ <space>... ] }... ] <quote>
  
  <hexit> ::=
    <digit> | A | B | C | D | E | F | a | b | c | d | e | f