introduce a @DialectOverride annotation

This allows the use of native SQL in annotations of portable programs.

We've needed something like this for a long time.

Author: gavinking

documentation/src/test/java/org/hibernate/userguide/schema/ColumnDefaultTest.java

@@ -10,7 +10,9 @@
 import jakarta.persistence.Id;
 
 import org.hibernate.annotations.ColumnDefault;
+import org.hibernate.annotations.DialectOverride;
 import org.hibernate.annotations.DynamicInsert;
+import org.hibernate.dialect.HSQLDialect;
 import org.hibernate.orm.test.jpa.BaseEntityManagerFunctionalTestCase;
 
 import org.junit.Test;
@@ -57,7 +59,8 @@ public static class Person {
         @ColumnDefault("'N/A'")
         private String name;
 
-        @ColumnDefault("-1")
+        @ColumnDefault(value = "-1",
+            overrides = @DialectOverride(dialect = HSQLDialect.class, value = "-1*1") )
         private Long clientId;
 
         //Getter and setters omitted for brevity

hibernate-core/src/main/java/org/hibernate/annotations/Check.java

@@ -26,4 +26,10 @@
 	 * The check constraints string.
 	 */
 	String constraints();
+	/**
+	 * A list of SQL constraints that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #constraints()}.
+	 */
+	DialectOverride[] overrides() default {};
 }

hibernate-core/src/main/java/org/hibernate/annotations/ColumnDefault.java

@@ -25,4 +25,10 @@
 	 * The DEFAULT definition to apply to the DDL.
 	 */
 	String value();
+	/**
+	 * A list of SQL expressions that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #value()}.
+	 */
+	DialectOverride[] overrides() default {};
 }

hibernate-core/src/main/java/org/hibernate/annotations/DialectOverride.java

@@ -0,0 +1,44 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.annotations;
+
+import org.hibernate.dialect.Dialect;
+
+import java.lang.annotation.Retention;
+
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
+/**
+ * Defines a SQL expression or fragment of SQL that should be used in a given dialect.
+ * Allows a portable program to embed unportable native SQL in annotations.
+ *
+ * @see Formula#overrides()
+ * @see JoinFormula#overrides()
+ * @see DiscriminatorFormula#overrides()
+ * @see Check#overrides()
+ * @see ColumnDefault#overrides()
+ * @see Filter#overrides()
+ * @see FilterDef#overrides()
+ * @see Where#overrides()
+ * @see OrderBy#overrides()
+ *
+ * @author Gavin King
+ */
+@Retention(RUNTIME)
+public @interface DialectOverride {
+	/**
+	 * The {@link Dialect} to which this override applies.
+	 *
+	 * @return the concrete Java class of the {@code Dialect}
+	 */
+	Class<? extends Dialect> dialect();
+
+	/**
+	 * The SQL expression or SQL fragment that should be used in the specified dialect.
+	 */
+	String value();
+}

hibernate-core/src/main/java/org/hibernate/annotations/DiscriminatorFormula.java

@@ -30,4 +30,10 @@
 	 * The formula string.
 	 */
 	String value();
+	/**
+	 * A list of SQL formulas that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #value()}.
+	 */
+	DialectOverride[] overrides() default {};
 }

hibernate-core/src/main/java/org/hibernate/annotations/Filter.java

@@ -48,4 +48,11 @@
 	 * The alias descriptors for injection.
 	 */
 	SqlFragmentAlias[] aliases() default {};
+
+	/**
+	 * A list of SQL conditions that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #condition()}.
+	 */
+	DialectOverride[] overrides() default {};
 }

hibernate-core/src/main/java/org/hibernate/annotations/FilterDef.java

@@ -37,4 +37,11 @@
 	 * The filter parameter definitions.
 	 */
 	ParamDef[] parameters() default {};
+
+	/**
+	 * A list of SQL conditions that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #defaultCondition()}.
+	 */
+	DialectOverride[] overrides() default {};
 }

hibernate-core/src/main/java/org/hibernate/annotations/Formula.java

@@ -50,4 +50,10 @@
 	 * The formula string.
 	 */
 	String value();
+	/**
+	 * A list of SQL formulas that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #value()}.
+	 */
+	DialectOverride[] overrides() default {};
 }

hibernate-core/src/main/java/org/hibernate/annotations/JoinFormula.java

@@ -31,4 +31,11 @@
 	 * The column this formula references.
 	 */
 	String referencedColumnName() default "";
+
+	/**
+	 * A list of SQL formulas that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #value()}.
+	 */
+	DialectOverride[] overrides() default {};
 }

hibernate-core/src/main/java/org/hibernate/annotations/OrderBy.java

@@ -32,4 +32,10 @@
 	 * SQL ordering clause.
 	 */
 	String clause();
+	/**
+	 * A list of SQL ordering expressions that should be used in the specified dialects.
+	 *
+	 * Overrides the default {@link #clause()}.
+	 */
+	DialectOverride[] overrides() default {};
 }