Remove optional seed from ES|QL SAMPLE

x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/operator/SampleOperator.java

@@ -9,6 +9,7 @@
 
 import org.elasticsearch.TransportVersion;
 import org.elasticsearch.TransportVersions;
+import org.elasticsearch.common.Randomness;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.io.stream.StreamInput;
@@ -27,16 +28,29 @@
 
 public class SampleOperator implements Operator {
 
- public record Factory(double probability, int seed) implements OperatorFactory {
+ public static class Factory implements OperatorFactory {
+
+ private final double probability;
+ private final Integer seed;
+
+ public Factory(double probability) {
+ this(probability, null);
+ }
+
+ // visible for testing
+ Factory(double probability, Integer seed) {
+ this.probability = probability;
+ this.seed = seed;
+ }
 
  @Override
  public SampleOperator get(DriverContext driverContext) {
- return new SampleOperator(probability, seed);
+ return new SampleOperator(probability, seed == null ? Randomness.get().nextInt() : seed);
  }
 
  @Override
  public String describe() {
- return "SampleOperator[probability = " + probability + ", seed = " + seed + "]";
+ return "SampleOperator[probability = " + probability + "]";
  }
  }
 

x-pack/plugin/esql/compute/src/test/java/org/elasticsearch/compute/operator/SampleOperatorTests.java

@@ -21,7 +21,6 @@
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.greaterThan;
 import static org.hamcrest.Matchers.lessThan;
-import static org.hamcrest.Matchers.matchesPattern;
 
 public class SampleOperatorTests extends OperatorTestCase {
 
@@ -46,7 +45,7 @@ protected SampleOperator.Factory simple(SimpleOptions options) {
 
  @Override
  protected Matcher<String> expectedDescriptionOfSimple() {
- return matchesPattern("SampleOperator\\[probability = 0.5, seed = -?\\d+]");
+ return equalTo("SampleOperator[probability = 0.5]");
  }
 
  @Override

x-pack/plugin/esql/src/main/antlr/EsqlBaseParser.g4

@@ -312,5 +312,5 @@ completionCommand
  ;
 
 sampleCommand
- : DEV_SAMPLE probability=decimalValue seed=integerValue?
+ : DEV_SAMPLE probability=decimalValue
  ;

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/optimizer/rules/logical/PushDownAndCombineSample.java

@@ -62,8 +62,7 @@ protected LogicalPlan rule(Sample sample, LogicalOptimizerContext context) {
  var child = sample.child();
  if (child instanceof Sample sampleChild) {
  var probability = combinedProbability(context, sample, sampleChild);
- var seed = combinedSeed(context, sample, sampleChild);
- plan = new Sample(sample.source(), probability, seed, sampleChild.child());
+ plan = new Sample(sample.source(), probability, sampleChild.child());
  } else if (child instanceof Enrich
  || child instanceof Eval
  || child instanceof Filter
@@ -82,22 +81,4 @@ private static Expression combinedProbability(LogicalOptimizerContext context, S
  var childProbability = (double) Foldables.valueOf(context.foldCtx(), child.probability());
  return Literal.of(parent.probability(), parentProbability * childProbability);
  }
-
- private static Expression combinedSeed(LogicalOptimizerContext context, Sample parent, Sample child) {
- var parentSeed = parent.seed();
- var childSeed = child.seed();
- Expression seed;
- if (parentSeed != null) {
- if (childSeed != null) {
- var seedValue = (int) Foldables.valueOf(context.foldCtx(), parentSeed);
- seedValue ^= (int) Foldables.valueOf(context.foldCtx(), childSeed);
- seed = Literal.of(parentSeed, seedValue);
- } else {
- seed = parentSeed;
- }
- } else {
- seed = childSeed;
- }
- return seed;
- }
 }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/optimizer/rules/physical/local/PushSampleToSource.java

@@ -33,9 +33,6 @@ protected PhysicalPlan rule(SampleExec sample, LocalPhysicalOptimizerContext ctx
  }
 
  var sampleQuery = new RandomSamplingQueryBuilder((double) Foldables.valueOf(ctx.foldCtx(), sample.probability()));
- if (sample.seed() != null) {
- sampleQuery.seed((int) Foldables.valueOf(ctx.foldCtx(), sample.seed()));
- }
 
  fullQuery.filter(sampleQuery);