Allow dialects to determine if they support savepoints

src/main/java/com/iciql/Db.java

@@ -572,7 +572,7 @@ public class Db implements AutoCloseable {
 	Savepoint prepareSavepoint() {
 		// don't change auto-commit mode.
 		// don't create save point.
-		if (!autoSavePoint) {
+		if (!autoSavePoint || !dialect.supportsSavePoints()) {
 			return null;
 		}
 		// create a savepoint

src/main/java/com/iciql/SQLDialect.java

@@ -72,6 +72,13 @@ public interface SQLDialect {
 	 */
 	void configureDialect(String databaseName, DatabaseMetaData data);
 
+	/**
+	 * Returns true if savepoints are supported.
+	 *
+	 * @return true if savepoints may be used.
+	 */
+	boolean supportsSavePoints();
+
 	/**
 	 * Allows a dialect to substitute an SQL type.
 	 *

src/main/java/com/iciql/SQLDialectDefault.java

@@ -74,6 +74,11 @@ public class SQLDialectDefault implements SQLDialect {
 		}
 	}
 
+	@Override
+	public boolean supportsSavePoints() {
+		return true;
+	}
+
 	/**
 	 * Allows subclasses to change the type of a column for a CREATE statement.
 	 *
@@ -398,101 +403,4 @@ public class SQLDialectDefault implements SQLDialect {
 		return o.toString();
 	}
 
-	@SuppressWarnings("incomplete-switch")
-	@Override
-	public void prepareCreateConstraintForeignKey(SQLStatement stat, String schemaName, String tableName, ConstraintForeignKeyDefinition constraint) {
-		StatementBuilder buff = new StatementBuilder();
-		buff.append("ALTER TABLE ");
-		buff.append(prepareTableName(schemaName, tableName));
-		buff.append(" ADD CONSTRAINT ");
-		buff.append(constraint.constraintName);
-		buff.append(" FOREIGN KEY ");
-		buff.append(" (");
-		for (String col : constraint.foreignColumns) {
-			buff.appendExceptFirst(", ");
-			buff.append(prepareColumnName(col));
-		}
-		buff.append(") ");
-		buff.append(" REFERENCES ");
-		buff.append(constraint.referenceTable);
-		buff.append(" (");
-		buff.resetCount();
-		for (String col : constraint.referenceColumns) {
-			buff.appendExceptFirst(", ");
-			buff.append(prepareColumnName(col));
-		}
-		buff.append(") ");
-		if (constraint.deleteType != ConstraintDeleteType.UNSET) {
-			buff.append(" ON DELETE ");
-			switch (constraint.deleteType) {
-			case CASCADE:
-				buff.append("CASCADE ");
-				break;
-			case RESTRICT:
-				buff.append("RESTRICT ");
-				break;
-			case SET_NULL:
-				buff.append("SET NULL ");
-				break;
-			case NO_ACTION:
-				buff.append("NO ACTION ");
-				break;
-			case SET_DEFAULT:
-				buff.append("SET DEFAULT ");
-				break;
-			}
-		}
-		if (constraint.updateType != ConstraintUpdateType.UNSET) {
-			buff.append(" ON UPDATE ");
-			switch (constraint.updateType) {
-			case CASCADE:
-				buff.append("CASCADE ");
-				break;
-			case RESTRICT:
-				buff.append("RESTRICT ");
-				break;
-			case SET_NULL:
-				buff.append("SET NULL ");
-				break;
-			case NO_ACTION:
-				buff.append("NO ACTION ");
-				break;
-			case SET_DEFAULT:
-				buff.append("SET DEFAULT ");
-				break;
-			}
-		}
-		switch (constraint.deferrabilityType) {
-		case DEFERRABLE_INITIALLY_DEFERRED:
-			buff.append("DEFERRABLE INITIALLY DEFERRED ");
-			break;
-		case DEFERRABLE_INITIALLY_IMMEDIATE:
-			buff.append("DEFERRABLE INITIALLY IMMEDIATE ");
-			break;
-		case NOT_DEFERRABLE:
-			buff.append("NOT DEFERRABLE ");
-			break;
-		case UNSET:
-			break;
-		}
-		stat.setSQL(buff.toString().trim());
-	}
-
-	@Override
-	public void prepareCreateConstraintUnique(SQLStatement stat, String schemaName, String tableName, ConstraintUniqueDefinition constraint) {
-		StatementBuilder buff = new StatementBuilder();
-		buff.append("ALTER TABLE ");
-		buff.append(prepareTableName(schemaName, tableName));
-		buff.append(" ADD CONSTRAINT ");
-		buff.append(constraint.constraintName);
-		buff.append(" UNIQUE ");
-		buff.append(" (");
-		for (String col : constraint.uniqueColumns) {
-			buff.appendExceptFirst(", ");
-			buff.append(prepareColumnName(col));
-		}
-		buff.append(") ");
-		stat.setSQL(buff.toString().trim());
-	}
-
 }