disable constraints while truncating tables on Informix

Author: gavinking

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/InformixDialect.java

@@ -579,6 +579,21 @@ public boolean dropConstraints() {
 		return !getVersion().isSameOrAfter( 12, 10 );
 	}
 
+	@Override
+	public boolean canDisableConstraints() {
+		return true;
+	}
+
+	@Override
+	public String getDisableConstraintStatement(String tableName, String name) {
+		return "set constraints " + name + " disabled";
+	}
+
+	@Override
+	public String getEnableConstraintStatement(String tableName, String name) {
+		return "set constraints " + name + " enabled";
+	}
+
 	@Override
 	public boolean supportsOrderByInSubquery() {
 		// This is just a guess