diff --git a/go.mod b/go.mod
index 49b71da6e..0b25d0725 100644
--- a/go.mod
+++ b/go.mod
@@ -43,3 +43,9 @@ require (
 	github.com/spf13/pflag v1.0.5 // indirect
 	golang.org/x/sys v0.13.0 // indirect
 )
+
+replace github.com/blevesearch/bleve_index_api => ../bleve_index_api
+
+replace github.com/blevesearch/scorch_segment_api/v2 => ../scorch_segment_api
+
+replace github.com/blevesearch/zapx/v16 => ../zapx
diff --git a/go.sum b/go.sum
index 1914f7919..f21c89611 100644
--- a/go.sum
+++ b/go.sum
@@ -2,8 +2,8 @@ github.com/RoaringBitmap/roaring v1.9.3 h1:t4EbC5qQwnisr5PrP9nt0IRhRTb9gMUgQF4t4
 github.com/RoaringBitmap/roaring v1.9.3/go.mod h1:6AXUsoIEzDTFFQCe1RbGA6uFONMhvejWj5rqITANK90=
 github.com/bits-and-blooms/bitset v1.12.0 h1:U/q1fAF7xXRhFCrhROzIfffYnu+dlS38vCZtmFVPHmA=
 github.com/bits-and-blooms/bitset v1.12.0/go.mod h1:7hO7Gc7Pp1vODcmWvKMRA9BNmbv6a/7QIWpPxHddWR8=
-github.com/blevesearch/bleve_index_api v1.2.1 h1:IuXwLvmyp7I7+e0FOA68gcHHLfzSQ4AqQ8wVab5uxk0=
-github.com/blevesearch/bleve_index_api v1.2.1/go.mod h1:rKQDl4u51uwafZxFrPD1R7xFOwKnzZW7s/LSeK4lgo0=
+github.com/blevesearch/bleve_index_api v1.2.0 h1:/DXMMWBwx/UmGKM1xDhTwDoJI5yQrG6rqRWPFcOgUVo=
+github.com/blevesearch/bleve_index_api v1.2.0/go.mod h1:PbcwjIcRmjhGbkS/lJCpfgVSMROV6TRubGGAODaK1W8=
 github.com/blevesearch/geo v0.1.20 h1:paaSpu2Ewh/tn5DKn/FB5SzvH0EWupxHEIwbCk/QPqM=
 github.com/blevesearch/geo v0.1.20/go.mod h1:DVG2QjwHNMFmjo+ZgzrIq2sfCh6rIHzy9d9d0B59I6w=
 github.com/blevesearch/go-faiss v1.0.24 h1:K79IvKjoKHdi7FdiXEsAhxpMuns0x4fM0BO93bW5jLI=
@@ -19,8 +19,8 @@ github.com/blevesearch/gtreap v0.1.1/go.mod h1:QaQyDRAT51sotthUWAH4Sj08awFSSWzgY
 github.com/blevesearch/mmap-go v1.0.2/go.mod h1:ol2qBqYaOUsGdm7aRMRrYGgPvnwLe6Y+7LMvAB5IbSA=
 github.com/blevesearch/mmap-go v1.0.4 h1:OVhDhT5B/M1HNPpYPBKIEJaD0F3Si+CrEKULGCDPWmc=
 github.com/blevesearch/mmap-go v1.0.4/go.mod h1:EWmEAOmdAS9z/pi/+Toxu99DnsbhG1TIxUoRmJw/pSs=
-github.com/blevesearch/scorch_segment_api/v2 v2.3.1 h1:jjexIzwOdBtC9MlUceNErYHepLvoKxTdA5atbeZSRWE=
-github.com/blevesearch/scorch_segment_api/v2 v2.3.1/go.mod h1:Np3Y03rsemM5TsyFxQ3wy+tG97EcviLTbp2S5W0tpRY=
+github.com/blevesearch/scorch_segment_api/v2 v2.3.0 h1:vxCjbXAkkEBSb4AB3Iqgr/EJcPyYRsiGxpcvsS8E1Dw=
+github.com/blevesearch/scorch_segment_api/v2 v2.3.0/go.mod h1:5y+TgXYSx+xJGaCwSlvy9G/UJBIY5wzvIkhvhBm2ATc=
 github.com/blevesearch/segment v0.9.1 h1:+dThDy+Lvgj5JMxhmOVlgFfkUtZV2kw49xax4+jTfSU=
 github.com/blevesearch/segment v0.9.1/go.mod h1:zN21iLm7+GnBHWTao9I+Au/7MBiL8pPFtJBJTsk6kQw=
 github.com/blevesearch/snowball v0.6.1 h1:cDYjn/NCH+wwt2UdehaLpr2e4BwLIjN4V/TdLsL+B5A=
@@ -33,18 +33,18 @@ github.com/blevesearch/upsidedown_store_api v1.0.2 h1:U53Q6YoWEARVLd1OYNc9kvhBMG
 github.com/blevesearch/upsidedown_store_api v1.0.2/go.mod h1:M01mh3Gpfy56Ps/UXHjEO/knbqyQ1Oamg8If49gRwrQ=
 github.com/blevesearch/vellum v1.1.0 h1:CinkGyIsgVlYf8Y2LUQHvdelgXr6PYuvoDIajq6yR9w=
 github.com/blevesearch/vellum v1.1.0/go.mod h1:QgwWryE8ThtNPxtgWJof5ndPfx0/YMBh+W2weHKPw8Y=
-github.com/blevesearch/zapx/v11 v11.3.11 h1:r6/wFHFAKWvXJb82f5aO53l6p+gRH6eiX7S1tb3VGc0=
-github.com/blevesearch/zapx/v11 v11.3.11/go.mod h1:0+gW+FaE48fNxoVtMY5ugtNHHof/PxCqh7CnhYdnMzQ=
-github.com/blevesearch/zapx/v12 v12.3.11 h1:GBBAmXesxXLV5UZ+FZ0qILb7HPssT+kxEkbPPfp5HPM=
-github.com/blevesearch/zapx/v12 v12.3.11/go.mod h1:0yeZg6JhaGxITlsS5co73aqPtM04+ycnI6D1v0mhbCs=
-github.com/blevesearch/zapx/v13 v13.3.11 h1:H5ZvgS1qM1XKzsAuwp3kvDfh5sJFu9bLH/B8U6Im5e8=
-github.com/blevesearch/zapx/v13 v13.3.11/go.mod h1:w2wjSDQ/WBVeEIvP0fvMJZAzDwqwIEzVPnCPrz93yAk=
-github.com/blevesearch/zapx/v14 v14.3.11 h1:pg+c/YFzMJ32GkOwLzH/HAQ/GBr6y1Ar7/K5ZQpxTNo=
-github.com/blevesearch/zapx/v14 v14.3.11/go.mod h1:qqyuR0u230jN1yMmE4FIAuCxmahRQEOehF78m6oTgns=
-github.com/blevesearch/zapx/v15 v15.3.18 h1:yJcQnQyHGNF6rAiwq85OHn3HaXo26t7vgd83RclEw7U=
-github.com/blevesearch/zapx/v15 v15.3.18/go.mod h1:vXRQzJJvlGVCdmOD5hg7t7JdjUT5DmDPhsAfjvtzIq8=
-github.com/blevesearch/zapx/v16 v16.1.11-0.20250107152255-021e66397612 h1:LhORiqEVyUPUrVETzmmVuT0Yudsz2R3qGLFJWUpMsQo=
-github.com/blevesearch/zapx/v16 v16.1.11-0.20250107152255-021e66397612/go.mod h1:+FIylxb+5Z/sFVmNaGpppGLHKBMUEnPSbkKoi+izER8=
+github.com/blevesearch/zapx/v11 v11.3.10 h1:hvjgj9tZ9DeIqBCxKhi70TtSZYMdcFn7gDb71Xo/fvk=
+github.com/blevesearch/zapx/v11 v11.3.10/go.mod h1:0+gW+FaE48fNxoVtMY5ugtNHHof/PxCqh7CnhYdnMzQ=
+github.com/blevesearch/zapx/v12 v12.3.10 h1:yHfj3vXLSYmmsBleJFROXuO08mS3L1qDCdDK81jDl8s=
+github.com/blevesearch/zapx/v12 v12.3.10/go.mod h1:0yeZg6JhaGxITlsS5co73aqPtM04+ycnI6D1v0mhbCs=
+github.com/blevesearch/zapx/v13 v13.3.10 h1:0KY9tuxg06rXxOZHg3DwPJBjniSlqEgVpxIqMGahDE8=
+github.com/blevesearch/zapx/v13 v13.3.10/go.mod h1:w2wjSDQ/WBVeEIvP0fvMJZAzDwqwIEzVPnCPrz93yAk=
+github.com/blevesearch/zapx/v14 v14.3.10 h1:SG6xlsL+W6YjhX5N3aEiL/2tcWh3DO75Bnz77pSwwKU=
+github.com/blevesearch/zapx/v14 v14.3.10/go.mod h1:qqyuR0u230jN1yMmE4FIAuCxmahRQEOehF78m6oTgns=
+github.com/blevesearch/zapx/v15 v15.3.17 h1:NkkMI98pYLq/uHnB6YWcITrrLpCVyvZ9iP+AyfpW1Ys=
+github.com/blevesearch/zapx/v15 v15.3.17/go.mod h1:vXRQzJJvlGVCdmOD5hg7t7JdjUT5DmDPhsAfjvtzIq8=
+github.com/blevesearch/zapx/v16 v16.1.11-0.20241219160422-82553cdd4b38 h1:iJ3Q3sbyo2d0bjfb720RmGjj7cqzh/EdP3528ggDIMY=
+github.com/blevesearch/zapx/v16 v16.1.11-0.20241219160422-82553cdd4b38/go.mod h1:JTZseJiEpogtkepKSubIKAmfgbQiOReJXfmjxB1qta4=
 github.com/couchbase/ghistogram v0.1.0 h1:b95QcQTCzjTUocDXp/uMgSNQi8oj1tGwnJ4bODWZnps=
 github.com/couchbase/ghistogram v0.1.0/go.mod h1:s1Jhy76zqfEecpNWJfWUiKZookAFaiGOEoyzgHt9i7k=
 github.com/couchbase/moss v0.2.0 h1:VCYrMzFwEryyhRSeI+/b3tRBSeTpi/8gn5Kf6dxqn+o=
diff --git a/index_test.go b/index_test.go
index c2844584a..0a781a189 100644
--- a/index_test.go
+++ b/index_test.go
@@ -3229,3 +3229,476 @@ func TestFuzzyScoring(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func TestDeletedFields(t *testing.T) {
+
+	indexMapping1 := NewIndexMapping()
+	def1 := `{
+		"analysis": {},
+		"default_analyzer": "standard",
+		"default_datetime_parser": "dateTimeOptional",
+		"default_field": "_all",
+		"default_mapping": {
+		  "dynamic": false,
+		  "enabled": true,
+		  "properties": {
+			"b": {
+			  "dynamic": false,
+			  "enabled": true,
+			  "fields": [
+				{
+				  "index": true,
+				  "name": "b",
+				  "store": true,
+				  "type": "text"
+				}
+			  ]
+			},
+			"c": {
+			  "dynamic": true,
+			  "enabled": true,
+			  "properties": {
+				"d": {
+				  "dynamic": false,
+				  "enabled": true,
+				  "fields": [
+					{
+					  "index": true,
+					  "name": "b",
+					  "store": true,
+					  "type": "text"
+					}
+				  ]
+				},
+				"e": {
+				  "dynamic": false,
+				  "enabled": true,
+				  "fields": [
+					{
+					  "index": true,
+					  "name": "e",
+					  "store": true,
+					  "type": "text"
+					}
+				  ]
+				},
+				"f": {
+				  "dynamic": false,
+				  "enabled": true,
+				  "properties": {
+					"g": {
+					  "dynamic": false,
+					  "enabled": true,
+					  "fields": [
+						{
+						  "index": true,
+						  "name": "g",
+						  "store": true,
+						  "type": "text"
+						}
+					  ]
+					},
+					"h": {
+					  "dynamic": false,
+					  "enabled": true,
+					  "fields": [
+						{
+						  "index": true,
+						  "name": "h",
+						  "store": true,
+						  "type": "text"
+						}
+					  ]
+					}
+				  }
+				}
+			  }
+			}
+		  }
+		},
+		"default_type": "_default",
+		"docvalues_dynamic": false,
+		"index_dynamic": true,
+		"store_dynamic": false,
+		"type_field": "_type",
+		"types": {
+		  "geo": {
+			"dynamic": false,
+			"enabled": true,
+			"properties": {
+			  "a": {
+				"dynamic": false,
+				"enabled": true,
+				"fields": [
+				  {
+					"index": true,
+					"name": "i",
+					"store": true,
+					"type": "text"
+				  }
+				]
+			  }
+			}
+		  },
+		  "geo2": {
+			"dynamic": true,
+			"enabled": true,
+			"properties": {
+			  "a": {
+				"dynamic": false,
+				"enabled": true,
+				"fields": [
+				  {
+					"index": true,
+					"name": "i",
+					"store": true,
+					"type": "text"
+				  }
+				]
+			  }
+			}
+		  }
+		}
+	  }`
+	err := indexMapping1.UnmarshalJSON([]byte(def1))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	indexMapping2 := NewIndexMapping()
+	def2 := `{
+		"analysis": {},
+		"default_analyzer": "standard",
+		"default_datetime_parser": "dateTimeOptional",
+		"default_field": "_all",
+		"default_mapping": {
+		  "dynamic": false,
+		  "enabled": true,
+		  "properties": {
+			"b": {
+			  "dynamic": false,
+			  "enabled": true,
+			  "fields": [
+				{
+				  "index": true,
+				  "name": "b",
+				  "store": true,
+				  "type": "text"
+				}
+			  ]
+			},
+			"c": {
+			  "dynamic": true,
+			  "enabled": true,
+			  "properties": {
+				"d": {
+				  "dynamic": false,
+				  "enabled": true,
+				  "fields": [
+					{
+					  "index": true,
+					  "name": "b",
+					  "store": true,
+					  "type": "text"
+					}
+				  ]
+				},
+				"e": {
+				  "dynamic": false,
+				  "enabled": true,
+				  "fields": [
+					{
+					  "index": true,
+					  "name": "e",
+					  "store": true,
+					  "type": "text"
+					}
+				  ]
+				},
+				"f": {
+				  "dynamic": false,
+				  "enabled": true,
+				  "properties": {
+					"h": {
+					  "dynamic": false,
+					  "enabled": true,
+					  "fields": [
+						{
+						  "index": true,
+						  "name": "h",
+						  "store": false,
+						  "type": "text"
+						}
+					  ]
+					}
+				  }
+				}
+			  }
+			}
+		  }
+		},
+		"default_type": "_default",
+		"docvalues_dynamic": false,
+		"index_dynamic": true,
+		"store_dynamic": false,
+		"type_field": "_type",
+		"types": {
+		  "geo": {
+			"dynamic": false,
+			"enabled": true,
+			"properties": {
+			  "a": {
+				"dynamic": false,
+				"enabled": true,
+				"fields": [
+				  {
+					"index": true,
+					"name": "i",
+					"store": true,
+					"type": "text"
+				  }
+				]
+			  }
+			}
+		  },
+		  "geo2": {
+			"dynamic": true,
+			"enabled": true,
+			"properties": {
+			  "a": {
+				"dynamic": false,
+				"enabled": true,
+				"fields": [
+				  {
+					"index": true,
+					"name": "i",
+					"store": true,
+					"type": "text"
+				  }
+				]
+			  }
+			}
+		  }
+		}
+	  }`
+	err = indexMapping2.UnmarshalJSON([]byte(def2))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, _ = DeletedFields(indexMapping1, indexMapping2)
+
+	fmt.Println(true)
+}
+
+func TestIndexUpdate(t *testing.T) {
+
+	indexMapping1 := NewIndexMapping()
+
+	def1 := `{
+		  		"default_analyzer": "standard",
+		  		"default_datetime_parser": "dateTimeOptional",
+		  		"default_field": "_all",
+		  		"default_mapping": {
+		   			"dynamic": false,
+		   			"enabled": false
+		  		},
+		  		"default_type": "_default",
+		  		"docvalues_dynamic": false,
+		  		"index_dynamic": false,
+		  		"store_dynamic": false,
+		  		"type_field": "_type",
+		  		"types": {
+		   			"_default._default": {
+						"dynamic": false,
+						"enabled": true,
+						"properties": {
+							"a": {
+								"enabled": true,
+								"dynamic": false,
+								"fields": [
+									{
+										"analyzer": "en",
+										"index": true,
+										"name": "a",
+										"type": "text",
+										"store": true
+									}
+								]
+							},
+							"b": {
+								"enabled": true,
+								"dynamic": false,
+								"fields": [
+									{
+										"analyzer": "en",
+										"index": true,
+										"name": "b",
+										"type": "text",
+										"store": true
+									}
+								]
+							},
+							"c": {
+								"enabled": true,
+								"dynamic": false,
+								"fields": [
+									{
+										"index": true,
+										"name": "c",
+										"type": "number",
+										"store": true
+									}
+								]
+							}
+						}
+					}
+				}
+			}`
+
+	err := indexMapping1.UnmarshalJSON([]byte(def1))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// TestIndex1-7 old ones
+	// TestIndex8 a, b, c with index and store
+	idx, err := New("/Users/likithb/Desktop/Code/MB-57888/TestIndex8", indexMapping1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer cleanupTmpIndexPath(t, "/Users/likithb/Desktop/Code/MB-57888/TestIndex8")
+
+	doc1 := map[string]interface{}{"a": "001", "b": "abc", "c": 12}
+	doc2 := map[string]interface{}{"a": "002", "b": "def", "c": 34}
+	doc3 := map[string]interface{}{"a": "003", "b": "ghi", "c": 56}
+	doc4 := map[string]interface{}{"a": "004", "b": "jkl", "c": 78}
+	doc5 := map[string]interface{}{"a": "005", "b": "mno", "c": 90}
+	doc6 := map[string]interface{}{"a": "006", "b": "pqr", "c": 21}
+	doc7 := map[string]interface{}{"a": "007", "b": "stu", "c": 43}
+	doc8 := map[string]interface{}{"a": "008", "b": "vwx", "c": 65}
+	doc9 := map[string]interface{}{"a": "009", "b": "yza", "c": 87}
+	doc10 := map[string]interface{}{"a": "0010", "b": "bcd", "c": 9}
+
+	batch := idx.NewBatch()
+	err = batch.Index("001", doc1)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("002", doc2)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("003", doc3)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("004", doc4)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("005", doc5)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("006", doc6)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("007", doc7)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("008", doc8)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("009", doc9)
+	if err != nil {
+		t.Error(err)
+	}
+	err = batch.Index("010", doc10)
+	if err != nil {
+		t.Error(err)
+	}
+	err = idx.Batch(batch)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = idx.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	def2 := `{
+				"default_analyzer": "standard",
+				"default_datetime_parser": "dateTimeOptional",
+				"default_field": "_all",
+				"default_mapping": {
+					"dynamic": false,
+					"enabled": false
+				},
+				"default_type": "_default",
+				"docvalues_dynamic": false,
+				"index_dynamic": false,
+				"store_dynamic": false,
+				"type_field": "_type",
+				"types": {
+					"_default._default": {
+						"dynamic": false,
+						"enabled": true,
+						"properties": {
+							"a": {
+								"enabled": true,
+								"dynamic": false,
+								"fields": [
+									{
+										"analyzer": "en",
+										"index": true,
+										"name": "a",
+										"type": "text",
+										"store": true
+									}
+								]
+							},
+							"b": {
+								"enabled": true,
+								"dynamic": false,
+								"fields": [
+									{
+										"analyzer": "en",
+										"index": true,
+										"name": "b",
+										"type": "text",
+										"store": true
+									}
+								]
+							},
+							"c": {
+								"enabled": true,
+								"dynamic": false,
+								"fields": [
+									{
+										"index": true,
+										"name": "c",
+										"type": "number",
+										"store": false
+									}
+								]
+							}
+						}
+					}
+				}
+			}`
+
+	idx, err = Update("/Users/likithb/Desktop/Code/MB-57888/TestIndex8", def2)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = idx.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+}
diff --git a/index_update_test.go b/index_update_test.go
new file mode 100644
index 000000000..e1d02b4cf
--- /dev/null
+++ b/index_update_test.go
@@ -0,0 +1,372 @@
+//  Copyright (c) 2025 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package bleve
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/blevesearch/bleve/v2/mapping"
+	index "github.com/blevesearch/bleve_index_api"
+)
+
+// One full update test
+// with text, vector and synonym
+// verify updated index with a query
+// query should check index delete, docvalues delete, store delete and all delete
+// read the bolt file and the index snapshot as well
+// deleted field test
+// compare mappings test
+// compare field mappings test
+// benchmark simple queries before and after index update
+
+func TestCompareFieldMapping(t *testing.T) {
+	tests := []struct {
+		original       *mapping.FieldMapping
+		updated        *mapping.FieldMapping
+		defaultChanges *defaultInfo
+		indexFieldInfo *index.FieldInfo
+		changed        bool
+		err            bool
+	}{
+		{ // both nil => no op
+			original:       nil,
+			updated:        nil,
+			defaultChanges: nil,
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            false,
+		},
+		{ // updated nil => delete all
+			original: &mapping.FieldMapping{},
+			updated:  nil,
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: &index.FieldInfo{
+				All: true,
+			},
+			changed: true,
+			err:     false,
+		},
+		{ // type changed => not updatable
+			original: &mapping.FieldMapping{
+				Type: "text",
+			},
+			updated: &mapping.FieldMapping{
+				Type: "datetime",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // synonym source changed for text => not updatable
+			original: &mapping.FieldMapping{
+				Type:          "text",
+				SynonymSource: "a",
+			},
+			updated: &mapping.FieldMapping{
+				Type:          "text",
+				SynonymSource: "b",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // analyser changed for text => not updatable
+			original: &mapping.FieldMapping{
+				Type:     "text",
+				Analyzer: "a",
+			},
+			updated: &mapping.FieldMapping{
+				Type:     "text",
+				Analyzer: "b",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // default analyser changed when inherited => not updatable
+			original: &mapping.FieldMapping{
+				Type:     "text",
+				Analyzer: "inherit",
+			},
+			updated: &mapping.FieldMapping{
+				Type:     "text",
+				Analyzer: "inherit",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       true,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // default datetimeparser changed for inherited datetime field => not updatable
+			original: &mapping.FieldMapping{
+				Type:       "datetime",
+				DateFormat: "inherit",
+			},
+			updated: &mapping.FieldMapping{
+				Type:       "datetime",
+				DateFormat: "inherit",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: true,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // dims changed for vector => not updatable
+			original: &mapping.FieldMapping{
+				Type:                    "vector",
+				Dims:                    128,
+				Similarity:              "l2_norm",
+				VectorIndexOptimizedFor: "memory-efficient",
+			},
+			updated: &mapping.FieldMapping{
+				Type:                    "vector",
+				Dims:                    1024,
+				Similarity:              "l2_norm",
+				VectorIndexOptimizedFor: "memory-efficient",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // similarity changed for vectorbase64 => not updatable
+			original: &mapping.FieldMapping{
+				Type:                    "vectorbase64",
+				Similarity:              "l2_norm",
+				Dims:                    128,
+				VectorIndexOptimizedFor: "memory-efficient",
+			},
+			updated: &mapping.FieldMapping{
+				Type:                    "vectorbase64",
+				Similarity:              "dot_product",
+				Dims:                    128,
+				VectorIndexOptimizedFor: "memory-efficient",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // vectorindexoptimizedfor chagned for vector => not updatable
+			original: &mapping.FieldMapping{
+				Type:                    "vector",
+				Similarity:              "dot_product",
+				Dims:                    128,
+				VectorIndexOptimizedFor: "memory-efficient",
+			},
+			updated: &mapping.FieldMapping{
+				Type:                    "vector",
+				Similarity:              "dot_product",
+				Dims:                    128,
+				VectorIndexOptimizedFor: "latency",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // includeinall changed => not updatable
+			original: &mapping.FieldMapping{
+				Type:         "numeric",
+				IncludeInAll: true,
+			},
+			updated: &mapping.FieldMapping{
+				Type:         "numeric",
+				IncludeInAll: false,
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ //includetermvectors changed => not updatable
+			original: &mapping.FieldMapping{
+				Type:               "numeric",
+				IncludeTermVectors: false,
+			},
+			updated: &mapping.FieldMapping{
+				Type:               "numeric",
+				IncludeTermVectors: true,
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // store changed after all checks => updatable with store delete
+			original: &mapping.FieldMapping{
+				Type:         "numeric",
+				SkipFreqNorm: true,
+			},
+			updated: &mapping.FieldMapping{
+				Type:         "numeric",
+				SkipFreqNorm: false,
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: nil,
+			changed:        false,
+			err:            true,
+		},
+		{ // index changed after all checks => updatable with index and docvalues delete
+			original: &mapping.FieldMapping{
+				Type:  "geopoint",
+				Index: true,
+			},
+			updated: &mapping.FieldMapping{
+				Type:  "geopoint",
+				Index: false,
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: &index.FieldInfo{
+				Index:     true,
+				DocValues: true,
+			},
+			changed: true,
+			err:     false,
+		},
+		{ // docvalues changed after all checks => docvalues delete
+			original: &mapping.FieldMapping{
+				Type:      "numeric",
+				DocValues: true,
+			},
+			updated: &mapping.FieldMapping{
+				Type:      "numeric",
+				DocValues: false,
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: &index.FieldInfo{
+				DocValues: true,
+			},
+			changed: true,
+			err:     false,
+		},
+		{ // no relavent changes => continue but no op
+			original: &mapping.FieldMapping{
+				Name:                    "",
+				Type:                    "datetime",
+				Analyzer:                "a",
+				Store:                   true,
+				Index:                   false,
+				IncludeTermVectors:      true,
+				IncludeInAll:            false,
+				DateFormat:              "a",
+				DocValues:               false,
+				SkipFreqNorm:            true,
+				Dims:                    128,
+				Similarity:              "dot_product",
+				VectorIndexOptimizedFor: "memory-efficient",
+				SynonymSource:           "a",
+			},
+			updated: &mapping.FieldMapping{
+				Name:                    "",
+				Type:                    "datetime",
+				Analyzer:                "b",
+				Store:                   true,
+				Index:                   false,
+				IncludeTermVectors:      true,
+				IncludeInAll:            false,
+				DateFormat:              "a",
+				DocValues:               false,
+				SkipFreqNorm:            true,
+				Dims:                    256,
+				Similarity:              "l2_norm",
+				VectorIndexOptimizedFor: "latency",
+				SynonymSource:           "b",
+			},
+			defaultChanges: &defaultInfo{
+				analyzer:       false,
+				dateTimeParser: false,
+				synonymSource:  false,
+			},
+			indexFieldInfo: &index.FieldInfo{},
+			changed:        false,
+			err:            false,
+		},
+	}
+
+	for i, test := range tests {
+		rv, changed, err := compareFieldMapping(test.original, test.updated, test.defaultChanges)
+
+		if err == nil && test.err || err != nil && !test.err {
+			t.Errorf("Unexpected error value for test %d, expecting %s, got %v\n", i, test.err, err)
+		}
+		if changed != test.changed {
+			t.Errorf("Unexpected changed value for test %d, expecting %s, got %s\n", i, test.changed, changed)
+		}
+		if rv == nil && test.indexFieldInfo != nil || rv != nil && test.indexFieldInfo == nil || !reflect.DeepEqual(rv, test.indexFieldInfo) {
+			t.Errorf("Unexpected index field info value for test %d, expecting %+v, got %+v", i, test.indexFieldInfo, rv)
+		}
+	}
+}