batchupdate.html
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<TITLE>Executing a Batch of SQL Statements in a Database
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<h3>
e265.
Executing a Batch of SQL Statements in a Database</h3>
With batch updating, a set of SQL statements is assembled and then
sent altogether to the database for execution. Batch updating can
improve performance.
<P> This example creates a batch of insert statements. Auto-commit
is disabled so that you have the choice of committing or not in the
event of an exception.
<pre>
try {
// Disable auto-commit
<font color="#0066ff"><i>connection</i></font>.setAutoCommit(false);
// Create a prepared statement
String sql = <font color="#0066ff"><i>"INSERT INTO my_table VALUES(?)"</i></font>;
PreparedStatement pstmt = <font color="#0066ff"><i>connection</i></font>.prepareStatement(sql);
// Insert 10 rows of data
for (int i=0; i<10; i++) {
pstmt.setString(1, <font color="#0066ff"><i>""+i</i></font>);
pstmt.addBatch();
}
// Execute the batch
int [] updateCounts = pstmt.executeBatch();
// All statements were successfully executed.
// updateCounts contains one element for each batched statement.
// updateCounts[i] contains the number of rows affected by that statement.
processUpdateCounts(updateCounts);
// Since there were no errors, commit
<font color="#0066ff"><i>connection</i></font>.commit();
} catch (BatchUpdateException e) {
// Not all of the statements were successfully executed
int[] updateCounts = e.getUpdateCounts();
// Some databases will continue to execute after one fails.
// If so, updateCounts.length will equal the number of batched statements.
// If not, updateCounts.length will equal the number of successfully executed statements
processUpdateCounts(updateCounts);
// Either commit the successfully executed statements or rollback the entire batch
<font color="#0066ff"><i>connection</i></font>.rollback();
} catch (SQLException e) {
}
public static void processUpdateCounts(int[] updateCounts) {
for (int i=0; i<updateCounts.length; i++) {
if (updateCounts[i] >= 0) {
// Successfully executed; the number represents number of affected rows
} else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
// Successfully executed; number of affected rows not available
} else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
// Failed to execute
}
}
}
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Related Examples
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e264. <a class="eglink" href="CanBatch.html?l=rel">
Determining If a Database Supports Batching
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See also:
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Connections
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Deleting Data
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Drivers
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Importing and Exporting
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<a class="eglink" href="/egs/java.sql/pkg.html?l=rel#Inserting%20and%20Updating%20Data">
Inserting and Updating Data
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<a class="eglink" href="/egs/java.sql/pkg.html?l=rel#Oracle%20OBJECTs">
Oracle OBJECTs
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<a class="eglink" href="/egs/java.sql/pkg.html?l=rel#Oracle%20VARRAYs">
Oracle VARRAYs
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Procedures and Functions
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<a class="eglink" href="/egs/java.sql/pkg.html?l=rel#Retrieving%20Data">
Retrieving Data
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<a class="eglink" href="/egs/java.sql/pkg.html?l=rel#Scrollable%20Result%20Sets">
Scrollable Result Sets
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Tables
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<a class="eglink" href="/egs/java.sql/pkg.html?l=rel#Updatable%20Result%20Sets">
Updatable Result Sets
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