zstan commented on code in PR #13366:
URL: https://github.com/apache/ignite/pull/13366#discussion_r3750010472
##########
modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/exec/ExecutionServiceImpl.java:
##########
@@ -581,6 +601,388 @@ private FieldsQueryCursor<List<?>>
executeDdl(RootQuery<Row> qry, DdlPlan plan)
}
}
+ /**
+ * Executes a {@code SELECT ... FOR UPDATE} plan.
+ *
+ * <ol>
+ * <li>Validates that the current transaction is PESSIMISTIC.</li>
+ * <li>Runs the inner SELECT with hidden key, value, and version columns
and materialises all rows.</li>
+ * <li>Builds cache entries from the hidden columns.</li>
+ * <li>Creates a savepoint, acquires pessimistic locks via {@code
lockTxEntries()},
+ * and releases the savepoint on success (or rolls back on
failure).</li>
+ * <li>Repeats the SELECT and lock attempt after a concurrent version
change while the deadline permits.</li>
+ * <li>Returns a cursor with only the user-visible columns (the appended
_KEY is stripped).</li>
+ * </ol>
+ */
+ private FieldsQueryCursor<List<?>> executeForUpdate(RootQuery<Row> qry,
SelectForUpdatePlan plan) {
+ GridNearTxLocal userTx = Commons.queryTransaction(qry.context(),
ctx.cache().context());
+
+ if (userTx == null || !userTx.pessimistic())
+ throw new IgniteSQLException(
+
IgniteResource.INSTANCE.selectForUpdateRequiresPessimisticTx().str(),
+ IgniteQueryErrorCode.UNSUPPORTED_OPERATION);
+
+ long waitMs = waitMillis(plan);
+
+ // Zero means that retries are limited only by the transaction or
query timeout.
+ long lockAcquisitionEndTime = waitMs > 0
+ ? U.currentTimeMillis() + waitMs
+ : waitMs < 0 ? U.currentTimeMillis() : 0L;
+
+ RootQuery<Row> selectQry = qry;
+
+ while (true) {
+ FieldsQueryCursor<List<?>> cursor = tryExecuteForUpdate(selectQry,
plan, userTx, waitMs, lockAcquisitionEndTime);
+
+ if (cursor != null)
+ return cursor;
+
+ if (lockAcquisitionEndTime != 0 && U.currentTimeMillis() >=
lockAcquisitionEndTime) {
+ throw new IgniteSQLException(
+ IgniteResource.INSTANCE.selectForUpdateLockFailed().str(),
+ IgniteQueryErrorCode.CONCURRENT_UPDATE);
+ }
+
+ // The previous query has already been closed after execution, so
retry with a fresh root query.
+ selectQry = qry.retryQuery();
+ qryReg.register(selectQry);
+ }
+ }
+
+ /**
+ * Converts the SQL lock wait value to the internal millisecond
representation.
+ *
+ * @param plan SELECT FOR UPDATE plan.
+ * @return {@code 0} for the remaining transaction/query timeout, {@code
-1} for NOWAIT,
+ * or a positive timeout in milliseconds.
+ */
+ private static long waitMillis(SelectForUpdatePlan plan) {
+ // Convert SQL waitSeconds to the internal lock-wait representation:
+ // null means use the remaining transaction time or the query timeout
and is encoded as 0;
+ // 0 requests NOWAIT and is encoded as -1; a positive value is
converted from seconds to milliseconds.
+ Long waitSeconds = plan.waitSeconds();
+
+ if (waitSeconds == null)
+ return 0L;
+ else if (waitSeconds == 0L)
+ return -1L;
+ else
+ return waitSeconds * 1000L;
Review Comment:
rare case of course, but still valid !
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