diff --git a/jOOQ/src/main/java/org/jooq/InsertOnDuplicateSetStep.java b/jOOQ/src/main/java/org/jooq/InsertOnDuplicateSetStep.java
index 01582f0808..8c87dcb202 100644
--- a/jOOQ/src/main/java/org/jooq/InsertOnDuplicateSetStep.java
+++ b/jOOQ/src/main/java/org/jooq/InsertOnDuplicateSetStep.java
@@ -42,6 +42,7 @@ package org.jooq;
 import static org.jooq.SQLDialect.CUBRID;
 // ...
 import static org.jooq.SQLDialect.DERBY;
+import static org.jooq.SQLDialect.FIREBIRD;
 import static org.jooq.SQLDialect.H2;
 import static org.jooq.SQLDialect.HSQLDB;
 // ...
@@ -99,7 +100,7 @@ public interface InsertOnDuplicateSetStep<R extends Record> {
      * <code>ON DUPLICATE KEY UPDATE</code> or
      * <code>ON CONFLICT ... DO UPDATE</code> clause.
      */
-    @Support({ CUBRID, DERBY, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
+    @Support({ CUBRID, DERBY, FIREBIRD, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
     <T> InsertOnDuplicateSetMoreStep<R> set(Field<T> field, T value);
 
     /**
@@ -107,7 +108,7 @@ public interface InsertOnDuplicateSetStep<R extends Record> {
      * <code>ON DUPLICATE KEY UPDATE</code> or
      * <code>ON CONFLICT ... DO UPDATE</code> clause.
      */
-    @Support({ CUBRID, DERBY, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
+    @Support({ CUBRID, DERBY, FIREBIRD, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
     <T> InsertOnDuplicateSetMoreStep<R> set(Field<T> field, Field<T> value);
 
     /**
@@ -115,7 +116,7 @@ public interface InsertOnDuplicateSetStep<R extends Record> {
      * <code>ON DUPLICATE KEY UPDATE</code> or
      * <code>ON CONFLICT ... DO UPDATE</code> clause.
      */
-    @Support({ CUBRID, DERBY, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
+    @Support({ CUBRID, DERBY, FIREBIRD, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
     <T> InsertOnDuplicateSetMoreStep<R> set(Field<T> field, Select<? extends Record1<T>> value);
 
     /**
@@ -127,7 +128,7 @@ public interface InsertOnDuplicateSetStep<R extends Record> {
      * without the necessity of casting the Java <code>null</code> literal to
      * <code>(T)</code>.
      */
-    @Support({ CUBRID, DERBY, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
+    @Support({ CUBRID, DERBY, FIREBIRD, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
     <T> InsertOnDuplicateSetMoreStep<R> setNull(Field<T> field);
 
     /**
@@ -142,7 +143,7 @@ public interface InsertOnDuplicateSetStep<R extends Record> {
      * <code>Field&lt;T&gt;</code>. jOOQ will attempt to convert values to their
      * corresponding field's type.
      */
-    @Support({ CUBRID, DERBY, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
+    @Support({ CUBRID, DERBY, FIREBIRD, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
     InsertOnDuplicateSetMoreStep<R> set(Map<?, ?> map);
 
     /**
@@ -155,7 +156,7 @@ public interface InsertOnDuplicateSetStep<R extends Record> {
      *
      * @see #set(Map)
      */
-    @Support({ CUBRID, DERBY, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
+    @Support({ CUBRID, DERBY, FIREBIRD, H2, HSQLDB, MARIADB, MYSQL, POSTGRES, SQLITE })
     InsertOnDuplicateSetMoreStep<R> set(Record record);
 
 }
diff --git a/jOOQ/src/main/java/org/jooq/impl/InsertQueryImpl.java b/jOOQ/src/main/java/org/jooq/impl/InsertQueryImpl.java
index f291f319b6..c9c1ea2a3c 100644
--- a/jOOQ/src/main/java/org/jooq/impl/InsertQueryImpl.java
+++ b/jOOQ/src/main/java/org/jooq/impl/InsertQueryImpl.java
@@ -401,6 +401,7 @@ final class InsertQueryImpl<R extends Record> extends AbstractStoreQuery<R> impl
 
 
                 case DERBY:
+                case FIREBIRD:
                 case H2:
                 case HSQLDB: {
                     ctx.visit(toMerge(ctx.configuration()));