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copied!<p>As described in <a href="http://docs.oracle.com/cd/E11882_01/java.112/e16548/oraperf.htm#JJDBC28752" rel="nofollow noreferrer">Oracle's documentation</a>:</p> <blockquote> <p><strong>Prepared statements</strong>: The same statement is repeated with different bind variables.</p> <p><strong>Batch updates:</strong> You can reduce the number of round-trips to the database, thereby improving application performance, by grouping multiple UPDATE, DELETE, or INSERT statements into a single batch and having the whole batch sent to the database and processed in one trip. This is especially useful in combination with a prepared statement.</p> </blockquote> <p>As described in <a href="http://publib.boulder.ibm.com/infocenter/db2luw/v8/index.jsp?topic=/com.ibm.db2.udb.doc/ad/tjvbtupd.htm" rel="nofollow noreferrer">IBM's documentation</a> and taken from <a href="https://stackoverflow.com/a/14265302/734687">here</a>:</p> <blockquote> <p>The JDBC drivers that support JDBC 2.0 and above support batch updates. With batch updates, instead of updating rows of a DB2(R) table one at a time, you can direct JDBC to execute a group of updates at the same time. Statements that can be included in the same batch of updates are known as batchable statements.</p> <p><strong>If a statement has input parameters or host expressions, you can include that statement only in a batch that has other instances of the same statement</strong>. This type of batch is known as a <strong>homogeneous batch</strong>. If a statement has no input parameters, you can include that statement in a batch only if the other statements in the batch have no input parameters or host expressions. This type of batch is known as a <strong>heterogeneous batch</strong>. Two statements that can be included in the same batch are known as batch compatible.</p> </blockquote> <p>This means that your request is not possible. The only advantage you can get is performance improvement of batching the same type of statements AND preparing only once:</p> <p>When you execute a single SQL statement the database performs the following actions:</p> <ul> <li>prepare the statement</li> <li>bind the parameters</li> <li>execute the statement</li> </ul> <p>When you use batch commands the following happens:</p> <ul> <li>prepare the statement (all received in a single transmission)</li> <li>for all following identical statements with different parameters <ul> <li>bind the parameters</li> <li>execute the statement</li> </ul></li> </ul> <p>Since the preparation is performed only once you save time.</p> <p>But you can sort and split the commands:</p> <pre><code>sql.withBatch(20, "insert into t1 values(:a, :b)") { ... } sql.withBatch(20, "insert into t2 values(:c)") { ... } </code></pre> <p>BTW, what will compile is</p> <pre><code>sql.withBatch {ps -> ps.addBatch("insert into t1 values(1, 2)") ps.addBatch("insert into t2 values(3)") } </code></pre> <p>But in this case I am curious what will happen: I expect that the JDBC driver will simply not use batching.</p>

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