Esql dimension aware attributes

benchmarks/src/main/java/org/elasticsearch/benchmark/_nightly/esql/QueryPlanningBenchmark.java

@@ -92,7 +92,8 @@ public void setup() {
         var fields = 10_000;
         var mapping = LinkedHashMap.<String, EsField>newLinkedHashMap(fields);
         for (int i = 0; i < fields; i++) {
-            mapping.put("field" + i, new EsField("field-" + i, TEXT, emptyMap(), true));
+            // We're creating a standard index, so none of these fields should be marked as dimensions.
+            mapping.put("field" + i, new EsField("field-" + i, TEXT, emptyMap(), true, EsField.TimeSeriesFieldType.NONE));
         }
 
         var esIndex = new EsIndex("test", mapping, Map.of("test", IndexMode.STANDARD));

benchmarks/src/main/java/org/elasticsearch/benchmark/compute/operator/EvalBenchmark.java

@@ -212,7 +212,7 @@ private static EvalOperator.ExpressionEvaluator evaluator(String operation) {
                 FieldAttribute timestamp = new FieldAttribute(
                     Source.EMPTY,
                     "timestamp",
-                    new EsField("timestamp", DataType.DATETIME, Map.of(), true)
+                    new EsField("timestamp", DataType.DATETIME, Map.of(), true, EsField.TimeSeriesFieldType.NONE)
                 );
                 yield EvalMapper.toEvaluator(
                     FOLD_CONTEXT,
@@ -321,19 +321,35 @@ private static EvalOperator.ExpressionEvaluator evaluator(String operation) {
     }
 
     private static FieldAttribute longField() {
-        return new FieldAttribute(Source.EMPTY, "long", new EsField("long", DataType.LONG, Map.of(), true));
+        return new FieldAttribute(
+            Source.EMPTY,
+            "long",
+            new EsField("long", DataType.LONG, Map.of(), true, EsField.TimeSeriesFieldType.NONE)
+        );
     }
 
     private static FieldAttribute doubleField() {
-        return new FieldAttribute(Source.EMPTY, "double", new EsField("double", DataType.DOUBLE, Map.of(), true));
+        return new FieldAttribute(
+            Source.EMPTY,
+            "double",
+            new EsField("double", DataType.DOUBLE, Map.of(), true, EsField.TimeSeriesFieldType.NONE)
+        );
     }
 
     private static FieldAttribute intField() {
-        return new FieldAttribute(Source.EMPTY, "int", new EsField("int", DataType.INTEGER, Map.of(), true));
+        return new FieldAttribute(
+            Source.EMPTY,
+            "int",
+            new EsField("int", DataType.INTEGER, Map.of(), true, EsField.TimeSeriesFieldType.NONE)
+        );
     }
 
     private static FieldAttribute keywordField() {
-        return new FieldAttribute(Source.EMPTY, "keyword", new EsField("keyword", DataType.KEYWORD, Map.of(), true));
+        return new FieldAttribute(
+            Source.EMPTY,
+            "keyword",
+            new EsField("keyword", DataType.KEYWORD, Map.of(), true, EsField.TimeSeriesFieldType.NONE)
+        );
     }
 
     private static Configuration configuration() {

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/expression/Attribute.java

@@ -149,4 +149,9 @@ public static boolean dataTypeEquals(List<Attribute> left, List<Attribute> right
         }
         return true;
     }
+
+    /**
+     * @return true if the attribute represents a TSDB dimension type
+     */
+    public abstract boolean isDimension();
 }

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/expression/EmptyAttribute.java

@@ -44,6 +44,11 @@ protected String label() {
         return "e";
     }
 
+    @Override
+    public boolean isDimension() {
+        return false;
+    }
+
     @Override
     public boolean resolved() {
         return true;

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/expression/FieldAttribute.java

@@ -216,6 +216,11 @@ protected String label() {
         return "f";
     }
 
+    @Override
+    public boolean isDimension() {
+        return field.getTimeSeriesFieldType() == EsField.TimeSeriesFieldType.DIMENSION;
+    }
+
     public EsField field() {
         return field;
     }

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/expression/MetadataAttribute.java

@@ -120,6 +120,11 @@ protected String label() {
         return "m";
     }
 
+    @Override
+    public boolean isDimension() {
+        return false;
+    }
+
     @Override
     protected NodeInfo<? extends Expression> info() {
         return NodeInfo.create(this, MetadataAttribute::new, name(), dataType(), nullable(), id(), synthetic(), searchable);

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/expression/ReferenceAttribute.java

@@ -117,4 +117,9 @@ protected NodeInfo<ReferenceAttribute> info() {
     protected String label() {
         return "r";
     }
+
+    @Override
+    public boolean isDimension() {
+        return false;
+    }
 }

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/expression/UnresolvedAttribute.java

@@ -107,6 +107,11 @@ protected String label() {
         return UNRESOLVED_PREFIX;
     }
 
+    @Override
+    public boolean isDimension() {
+        return false;
+    }
+
     @Override
     public String nodeString() {
         return toString();

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/DateEsField.java

@@ -20,8 +20,8 @@
  */
 public class DateEsField extends EsField {
 
-    public static DateEsField dateEsField(String name, Map<String, EsField> properties, boolean hasDocValues) {
-        return new DateEsField(name, DataType.DATETIME, properties, hasDocValues, TimeSeriesFieldType.UNKNOWN);
+    public static DateEsField dateEsField(String name, Map<String, EsField> properties, boolean hasDocValues, TimeSeriesFieldType tsType) {
+        return new DateEsField(name, DataType.DATETIME, properties, hasDocValues, tsType);
     }
 
     private DateEsField(

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/EsField.java

@@ -7,6 +7,7 @@
 package org.elasticsearch.xpack.esql.core.type;
 
 import org.elasticsearch.TransportVersions;
+import org.elasticsearch.action.fieldcaps.IndexFieldCapabilities;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
@@ -31,10 +32,36 @@ public class EsField implements Writeable {
      * roles within the ESQL query processing pipeline.
      */
     public enum TimeSeriesFieldType implements Writeable {
-        UNKNOWN(0),
-        NONE(1),
-        METRIC(2),
-        DIMENSION(3);
+        UNKNOWN(0) {
+            @Override
+            public TimeSeriesFieldType merge(TimeSeriesFieldType other) {
+                return other;
+            }
+        },
+        NONE(1) {
+            @Override
+            public TimeSeriesFieldType merge(TimeSeriesFieldType other) {
+                return other;
+            }
+        },
+        METRIC(2) {
+            @Override
+            public TimeSeriesFieldType merge(TimeSeriesFieldType other) {
+                if (other != DIMENSION) {
+                    return METRIC;
+                }
+                throw new IllegalStateException("Time Series Metadata conflict.  Cannot merge [" + other + "] with [METRIC].");
+            }
+        },
+        DIMENSION(3) {
+            @Override
+            public TimeSeriesFieldType merge(TimeSeriesFieldType other) {
+                if (other != METRIC) {
+                    return DIMENSION;
+                }
+                throw new IllegalStateException("Time Series Metadata conflict.  Cannot merge [" + other + "] with [DIMENSION].");
+            }
+        };
 
         private final int id;
 
@@ -57,6 +84,19 @@ public static TimeSeriesFieldType readFromStream(StreamInput in) throws IOExcept
                 default -> throw new IOException("Unexpected value for TimeSeriesFieldType: " + id);
             };
         }
+
+        public static TimeSeriesFieldType fromIndexFieldCapabilities(IndexFieldCapabilities capabilities) {
+            if (capabilities.isDimension()) {
+                assert capabilities.metricType() == null;
+                return DIMENSION;
+            }
+            if (capabilities.metricType() != null) {
+                return METRIC;
+            }
+            return NONE;
+        }
+
+        public abstract TimeSeriesFieldType merge(TimeSeriesFieldType other);
     }
 
     private static Map<String, Reader<? extends EsField>> readers = Map.ofEntries(
@@ -83,13 +123,8 @@ public static Reader<? extends EsField> getReader(String name) {
     private final Map<String, EsField> properties;
     private final String name;
     private final boolean isAlias;
-    // Because the subclasses all reimplement serialization, this needs to be writeable from subclass constructors
     private final TimeSeriesFieldType timeSeriesFieldType;
 
-    public EsField(String name, DataType esDataType, Map<String, EsField> properties, boolean aggregatable) {
-        this(name, esDataType, properties, aggregatable, false, TimeSeriesFieldType.UNKNOWN);
-    }
-
     public EsField(
         String name,
         DataType esDataType,
@@ -100,10 +135,6 @@ public EsField(
         this(name, esDataType, properties, aggregatable, false, timeSeriesFieldType);
     }
 
-    public EsField(String name, DataType esDataType, Map<String, EsField> properties, boolean aggregatable, boolean isAlias) {
-        this(name, esDataType, properties, aggregatable, isAlias, TimeSeriesFieldType.UNKNOWN);
-    }
-
     public EsField(
         String name,
         DataType esDataType,
@@ -247,6 +278,10 @@ public Exact getExactInfo() {
         return Exact.EXACT_FIELD;
     }
 
+    public TimeSeriesFieldType getTimeSeriesFieldType() {
+        return timeSeriesFieldType;
+    }
+
     @Override
     public String toString() {
         return name + "@" + esDataType.typeName() + "=" + properties;
@@ -265,12 +300,13 @@ public boolean equals(Object o) {
             && isAlias == field.isAlias
             && esDataType == field.esDataType
             && Objects.equals(name, field.name)
-            && Objects.equals(properties, field.properties);
+            && Objects.equals(properties, field.properties)
+            && Objects.equals(timeSeriesFieldType, field.timeSeriesFieldType);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(esDataType, aggregatable, properties, name, isAlias);
+        return Objects.hash(esDataType, aggregatable, properties, name, isAlias, timeSeriesFieldType);
     }
 
     public static final class Exact {

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/KeywordEsField.java

@@ -10,7 +10,6 @@
 import org.elasticsearch.common.io.stream.StreamOutput;
 
 import java.io.IOException;
-import java.util.Collections;
 import java.util.Map;
 import java.util.Objects;
 
@@ -26,23 +25,16 @@ public class KeywordEsField extends EsField {
     private final int precision;
     private final boolean normalized;
 
-    public KeywordEsField(String name) {
-        this(name, Collections.emptyMap(), true, Short.MAX_VALUE, false);
-    }
-
-    public KeywordEsField(String name, Map<String, EsField> properties, boolean hasDocValues, int precision, boolean normalized) {
-        this(name, properties, hasDocValues, precision, normalized, false);
-    }
-
     public KeywordEsField(
         String name,
         Map<String, EsField> properties,
         boolean hasDocValues,
         int precision,
         boolean normalized,
-        boolean isAlias
+        boolean isAlias,
+        TimeSeriesFieldType timeSeriesFieldType
     ) {
-        this(name, KEYWORD, properties, hasDocValues, precision, normalized, isAlias, TimeSeriesFieldType.UNKNOWN);
+        this(name, KEYWORD, properties, hasDocValues, precision, normalized, isAlias, timeSeriesFieldType);
     }
 
     protected KeywordEsField(

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/MultiTypeEsField.java

@@ -33,11 +33,6 @@ public class MultiTypeEsField extends EsField {
 
     private final Map<String, Expression> indexToConversionExpressions;
 
-    public MultiTypeEsField(String name, DataType dataType, boolean aggregatable, Map<String, Expression> indexToConversionExpressions) {
-        super(name, dataType, Map.of(), aggregatable);
-        this.indexToConversionExpressions = indexToConversionExpressions;
-    }
-
     public MultiTypeEsField(
         String name,
         DataType dataType,
@@ -99,7 +94,13 @@ public static MultiTypeEsField resolveFrom(
                 indexToConversionExpressions.put(indexName, convertExpr);
             }
         }
-        return new MultiTypeEsField(invalidMappedField.getName(), resolvedDataType, false, indexToConversionExpressions);
+        return new MultiTypeEsField(
+            invalidMappedField.getName(),
+            resolvedDataType,
+            false,
+            indexToConversionExpressions,
+            invalidMappedField.getTimeSeriesFieldType()
+        );
     }
 
     @Override

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/PotentiallyUnmappedKeywordEsField.java

@@ -9,6 +9,7 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 
 import java.io.IOException;
+import java.util.Collections;
 
 /**
  * This class is used as a marker for fields that may be unmapped, where an unmapped field is a field which exists in the _source but is not
@@ -17,7 +18,7 @@
  */
 public class PotentiallyUnmappedKeywordEsField extends KeywordEsField {
     public PotentiallyUnmappedKeywordEsField(String name) {
-        super(name);
+        super(name, Collections.emptyMap(), true, Short.MAX_VALUE, false, false, TimeSeriesFieldType.UNKNOWN);
     }
 
     public PotentiallyUnmappedKeywordEsField(StreamInput in) throws IOException {

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/TextEsField.java

@@ -25,14 +25,6 @@
  */
 public class TextEsField extends EsField {
 
-    public TextEsField(String name, Map<String, EsField> properties, boolean hasDocValues) {
-        this(name, properties, hasDocValues, false);
-    }
-
-    public TextEsField(String name, Map<String, EsField> properties, boolean hasDocValues, boolean isAlias) {
-        super(name, TEXT, properties, hasDocValues, isAlias, TimeSeriesFieldType.UNKNOWN);
-    }
-
     public TextEsField(
         String name,
         Map<String, EsField> properties,

x-pack/plugin/esql-core/src/test/java/org/elasticsearch/xpack/esql/core/util/TestUtils.java

@@ -54,15 +54,15 @@ public static FieldAttribute fieldAttribute() {
     }
 
     public static FieldAttribute fieldAttribute(String name, DataType type) {
-        return new FieldAttribute(EMPTY, name, new EsField(name, type, emptyMap(), randomBoolean()));
+        return new FieldAttribute(EMPTY, name, new EsField(name, type, emptyMap(), randomBoolean(), EsField.TimeSeriesFieldType.NONE));
     }
 
     public static FieldAttribute getFieldAttribute(String name) {
         return getFieldAttribute(name, INTEGER);
     }
 
     public static FieldAttribute getFieldAttribute(String name, DataType dataType) {
-        return new FieldAttribute(EMPTY, name, new EsField(name + "f", dataType, emptyMap(), true));
+        return new FieldAttribute(EMPTY, name, new EsField(name + "f", dataType, emptyMap(), true, EsField.TimeSeriesFieldType.NONE));
     }
 
     /**

x-pack/plugin/esql/qa/testFixtures/src/main/java/org/elasticsearch/xpack/esql/EsqlTestUtils.java

@@ -205,15 +205,15 @@ public static FieldAttribute getFieldAttribute(String name) {
     }
 
     public static FieldAttribute getFieldAttribute(String name, DataType dataType) {
-        return new FieldAttribute(EMPTY, name, new EsField(name + "f", dataType, emptyMap(), true));
+        return new FieldAttribute(EMPTY, name, new EsField(name + "f", dataType, emptyMap(), true, EsField.TimeSeriesFieldType.NONE));
     }
 
     public static FieldAttribute fieldAttribute() {
         return fieldAttribute(randomAlphaOfLength(10), randomFrom(DataType.types()));
     }
 
     public static FieldAttribute fieldAttribute(String name, DataType type) {
-        return new FieldAttribute(EMPTY, name, new EsField(name, type, emptyMap(), randomBoolean()));
+        return new FieldAttribute(EMPTY, name, new EsField(name, type, emptyMap(), randomBoolean(), EsField.TimeSeriesFieldType.NONE));
     }
 
     public static Literal of(Object value) {