diff --git a/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/H2.kt b/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/H2.kt
index b26c613c3e..bd1f333f0a 100644
--- a/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/H2.kt
+++ b/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/H2.kt
@@ -4,6 +4,7 @@ import org.intellij.lang.annotations.Language
 import org.jetbrains.exposed.exceptions.throwUnsupportedException
 import org.jetbrains.exposed.sql.*
 import org.jetbrains.exposed.sql.transactions.TransactionManager
+import java.util.*
 
 internal object H2DataTypeProvider : DataTypeProvider() {
     override fun binaryType(): String {
@@ -12,6 +13,7 @@ internal object H2DataTypeProvider : DataTypeProvider() {
     }
 
     override fun uuidType(): String = "UUID"
+    override fun uuidToDB(value: UUID): Any = value.toString()
     override fun dateTimeType(): String = "DATETIME(9)"
 
     override fun timestampWithTimeZoneType(): String = "TIMESTAMP(9) WITH TIME ZONE"
diff --git a/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/OracleDialect.kt b/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/OracleDialect.kt
index 42b08283f2..82e1ef05fb 100644
--- a/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/OracleDialect.kt
+++ b/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/OracleDialect.kt
@@ -3,6 +3,7 @@ package org.jetbrains.exposed.sql.vendors
 import org.jetbrains.exposed.exceptions.throwUnsupportedException
 import org.jetbrains.exposed.sql.*
 import org.jetbrains.exposed.sql.transactions.TransactionManager
+import java.util.*
 
 internal object OracleDataTypeProvider : DataTypeProvider() {
     override fun byteType(): String = "SMALLINT"
@@ -26,11 +27,25 @@ internal object OracleDataTypeProvider : DataTypeProvider() {
 
     override fun binaryType(length: Int): String {
         @Suppress("MagicNumber")
-        return if (length < 2000) "RAW ($length)"
-        else binaryType()
+        return if (length < 2000) "RAW ($length)" else binaryType()
+    }
+
+    override fun uuidType(): String {
+        return if ((currentDialect as? H2Dialect)?.h2Mode == H2Dialect.H2CompatibilityMode.Oracle) {
+            "UUID"
+        } else {
+            return "RAW(16)"
+        }
+    }
+
+    override fun uuidToDB(value: UUID): Any {
+        return if ((currentDialect as? H2Dialect)?.h2Mode == H2Dialect.H2CompatibilityMode.Oracle) {
+            H2DataTypeProvider.uuidToDB(value)
+        } else {
+            super.uuidToDB(value)
+        }
     }
 
-    override fun uuidType(): String = "RAW(16)"
     override fun dateTimeType(): String = "TIMESTAMP"
     override fun booleanType(): String = "CHAR(1)"
     override fun booleanToStatementString(bool: Boolean) = if (bool) "1" else "0"
diff --git a/exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/dml/UpsertTests.kt b/exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/dml/UpsertTests.kt
index ba24fdbbf1..554f95a621 100644
--- a/exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/dml/UpsertTests.kt
+++ b/exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/dml/UpsertTests.kt
@@ -63,17 +63,17 @@ class UpsertTests : DatabaseTestsBase() {
                     it[name] = "A"
                 }
 
-                tester.upsert {  // insert because only 1 constraint is equal
+                tester.upsert { // insert because only 1 constraint is equal
                     it[idA] = 7
                     it[idB] = insertStmt get tester.idB
                     it[name] = "B"
                 }
-                tester.upsert {  // insert because both constraints differ
+                tester.upsert { // insert because both constraints differ
                     it[idA] = 99
                     it[idB] = 99
                     it[name] = "C"
                 }
-                tester.upsert {  // update because both constraints match
+                tester.upsert { // update because both constraints match
                     it[idA] = insertStmt get tester.idA
                     it[idB] = insertStmt get tester.idB
                     it[name] = "D"
@@ -157,6 +157,32 @@ class UpsertTests : DatabaseTestsBase() {
         }
     }
 
+    @Test
+    fun testUpsertWithUUIDKeyConflict() {
+        val tester = object : Table("tester") {
+            val id = uuid("id").autoGenerate()
+            val title = text("title")
+
+            override val primaryKey = PrimaryKey(id)
+        }
+
+        withTables(tester) { testDb ->
+            excludingH2Version1(testDb) {
+                val uuid1 = tester.upsert {
+                    it[title] = "A"
+                } get tester.id
+                tester.upsert {
+                    it[id] = uuid1
+                    it[title] = "B"
+                }
+
+                val result = tester.selectAll().single()
+                assertEquals(uuid1, result[tester.id])
+                assertEquals("B", result[tester.title])
+            }
+        }
+    }
+
     @Test
     fun testUpsertWithNoUniqueConstraints() {
         val tester = object : Table("tester") {
@@ -254,18 +280,18 @@ class UpsertTests : DatabaseTestsBase() {
         withTables(tester) { testDb ->
             excludingH2Version1(testDb) {
                 val testWord = "Test"
-                tester.upsert {  // default expression in insert
+                tester.upsert { // default expression in insert
                     it[word] = testWord
                 }
                 assertEquals("Phrase", tester.selectAll().single()[tester.phrase])
 
                 val phraseConcat = concat(" - ", listOf(tester.word, tester.phrase))
-                tester.upsert(onUpdate = listOf(tester.phrase to phraseConcat)) {  // expression in update
+                tester.upsert(onUpdate = listOf(tester.phrase to phraseConcat)) { // expression in update
                     it[word] = testWord
                 }
                 assertEquals("$testWord - $defaultPhrase", tester.selectAll().single()[tester.phrase])
 
-                tester.upsert {  // provided expression in insert
+                tester.upsert { // provided expression in insert
                     it[word] = "$testWord 2"
                     it[phrase] = concat(stringLiteral("foo"), stringLiteral("bar"))
                 }