diff --git a/src/main/java/sirius/db/jdbc/constraints/SQLQueryCompiler.java b/src/main/java/sirius/db/jdbc/constraints/SQLQueryCompiler.java
index 32a48a641..d845d24e4 100644
--- a/src/main/java/sirius/db/jdbc/constraints/SQLQueryCompiler.java
+++ b/src/main/java/sirius/db/jdbc/constraints/SQLQueryCompiler.java
@@ -19,6 +19,7 @@
 import sirius.kernel.commons.Tuple;
 
 import java.util.List;
+import java.util.Optional;
 
 /**
  * Provides a query compiler for {@link sirius.db.jdbc.SmartQuery} and {@link SQLFilterFactory}.
@@ -42,22 +43,26 @@ public SQLQueryCompiler(FilterFactory<SQLConstraint> factory,
 
     @Override
     protected SQLConstraint compileSearchToken(Mapping field, QueryField.Mode mode, String value) {
+        Optional<String> caseOptimizedValue = getCaseOptimizedValue(field, value);
         switch (mode) {
             case EQUAL:
-                return factory.eq(field, value);
+                return factory.eq(field, caseOptimizedValue.orElse(value));
             case LIKE:
-                if (value.contains("*")) {
+                if (caseOptimizedValue.isEmpty() && value.contains("*")) {
                     return OMA.FILTERS.like(field).matches(value).ignoreCase().build();
                 } else {
-                    return factory.eq(field, value);
+                    return factory.eq(field, caseOptimizedValue.orElse(value));
                 }
             case PREFIX:
-                if (value.contains("*")) {
+                if (caseOptimizedValue.isEmpty() && value.contains("*")) {
                     return OMA.FILTERS.like(field).startsWith(value).ignoreCase().build();
                 } else {
-                    return OMA.FILTERS.like(field).startsWith(value).build();
+                    return OMA.FILTERS.like(field).startsWith(caseOptimizedValue.orElse(value)).build();
                 }
             default:
+                if (caseOptimizedValue.isPresent()) {
+                    return OMA.FILTERS.like(field).contains(caseOptimizedValue.get()).build();
+                }
                 return OMA.FILTERS.like(field).contains(value).ignoreCase().build();
         }
     }
diff --git a/src/main/java/sirius/db/mixing/annotations/LowerCase.java b/src/main/java/sirius/db/mixing/annotations/LowerCase.java
index f7c926159..ffeb35bc8 100644
--- a/src/main/java/sirius/db/mixing/annotations/LowerCase.java
+++ b/src/main/java/sirius/db/mixing/annotations/LowerCase.java
@@ -17,7 +17,8 @@
 /**
  * Marks a string property as auto lower-cased.
  * <p>
- * The value of this property will be lower-cased before it is written to the database.
+ * The value of this property will be lower-cased before it is written to the database. Also, it is used to optimize
+ * some system generated queries.
  */
 @Documented
 @Retention(RetentionPolicy.RUNTIME)
diff --git a/src/main/java/sirius/db/mixing/annotations/UpperCase.java b/src/main/java/sirius/db/mixing/annotations/UpperCase.java
index 10e8e305c..77bd4f27f 100644
--- a/src/main/java/sirius/db/mixing/annotations/UpperCase.java
+++ b/src/main/java/sirius/db/mixing/annotations/UpperCase.java
@@ -17,7 +17,8 @@
 /**
  * Marks a string property as auto upper-cased.
  * <p>
- * The value of this property will be upper-cased before it is written to the database.
+ * The value of this property will be upper-cased before it is written to the database. Also, it is used to optimize
+ * some system generated queries.
  */
 @Documented
 @Retention(RetentionPolicy.RUNTIME)
diff --git a/src/main/java/sirius/db/mixing/query/QueryCompiler.java b/src/main/java/sirius/db/mixing/query/QueryCompiler.java
index 666ff7a76..b08369409 100644
--- a/src/main/java/sirius/db/mixing/query/QueryCompiler.java
+++ b/src/main/java/sirius/db/mixing/query/QueryCompiler.java
@@ -11,6 +11,8 @@
 import sirius.db.mixing.EntityDescriptor;
 import sirius.db.mixing.Mapping;
 import sirius.db.mixing.Property;
+import sirius.db.mixing.annotations.LowerCase;
+import sirius.db.mixing.annotations.UpperCase;
 import sirius.db.mixing.properties.BaseEntityRefListProperty;
 import sirius.db.mixing.properties.BaseEntityRefProperty;
 import sirius.db.mixing.properties.LocalDateProperty;
@@ -35,6 +37,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -257,8 +260,7 @@ private C parseExpression() {
         skipWhitespace();
 
         if ((reader.current().is('!') || reader.current().is('-'))) {
-            if (reader.next().isWhitespace() ||reader.next()
-                                                     .isEndOfInput()) {
+            if (reader.next().isWhitespace() || reader.next().isEndOfInput()) {
                 // If there is a single "-" or "!" in a string like "foo - bar", we simly skip the dash
                 // as it is ignored by the indexing tokenizer anyway...
                 reader.consume();
@@ -789,4 +791,22 @@ private C parseTag() {
 
         return null;
     }
+
+    /**
+     * Returns the optimized value for the given field respecting the Sirius DB casing annotations.
+     *
+     * @param field the field to query for
+     * @param value the value to query
+     * @return the optimized value to use in a constraint if any, or an Optional.empty() if no optimization is possible
+     */
+    protected Optional<String> getCaseOptimizedValue(Mapping field, String value) {
+        Property property = resolveProperty(field.toString()).getSecond();
+        if (property.isAnnotationPresent(LowerCase.class)) {
+            return Optional.of(value.toLowerCase());
+        }
+        if (property.isAnnotationPresent(UpperCase.class)) {
+            return Optional.of(value.toUpperCase());
+        }
+        return Optional.empty();
+    }
 }
diff --git a/src/main/java/sirius/db/mixing/query/QueryField.java b/src/main/java/sirius/db/mixing/query/QueryField.java
index 3fc7a3763..5e0c6e665 100644
--- a/src/main/java/sirius/db/mixing/query/QueryField.java
+++ b/src/main/java/sirius/db/mixing/query/QueryField.java
@@ -24,8 +24,8 @@ public enum Mode {
         EQUAL, LIKE, PREFIX, CONTAINS
     }
 
-    private Mapping field;
-    private Mode mode;
+    private final Mapping field;
+    private final Mode mode;
 
     private QueryField(Mapping field, Mode mode) {
         this.field = field;
diff --git a/src/main/java/sirius/db/mongo/constraints/MongoQueryCompiler.java b/src/main/java/sirius/db/mongo/constraints/MongoQueryCompiler.java
index c82e1a921..d14182039 100644
--- a/src/main/java/sirius/db/mongo/constraints/MongoQueryCompiler.java
+++ b/src/main/java/sirius/db/mongo/constraints/MongoQueryCompiler.java
@@ -31,7 +31,7 @@ public class MongoQueryCompiler extends QueryCompiler<MongoConstraint> {
     private static final Mapping FULLTEXT_MAPPING = Mapping.named("$text");
 
     /**
-     * Represents an artificial field which generates a search using a <tt>$text</tt> filter. Therefore
+     * Represents an artificial field which generates a search using a <tt>$text</tt> filter. Therefore,
      * an appropriate <b>text</b> index has to be present.
      */
     public static final QueryField FULLTEXT = QueryField.contains(FULLTEXT_MAPPING);
@@ -58,7 +58,7 @@ protected MongoConstraint compileSearchToken(Mapping field, QueryField.Mode mode
         }
 
         if (mode == QueryField.Mode.EQUAL) {
-            return factory.eq(field, value);
+            return factory.eq(field, getCaseOptimizedValue(field, value).orElse(value));
         } else if (mode == QueryField.Mode.PREFIX) {
             return QueryBuilder.FILTERS.prefix(field, value);
         } else {