Check that expression is numeric before pushing down

Author: elasticsearchmachine

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/optimizer/rules/physical/local/PushTopNToSource.java

@@ -179,9 +179,10 @@ && canPushLimit(topNExec, plannerSettings)) {
                     distances.put(alias.id(), distance);
                 } else if (alias.child() instanceof Attribute attr) {
                     aliasReplacedByBuilder.put(alias.toAttribute(), attr.toAttribute());
-                } else if (alias.child().pushableOptions() == Expression.PushableOptions.PREFERRED) {
-                    pushableExpressions.put(alias.id(), alias);
-                }
+                } else if (alias.child().dataType().isNumeric()
+                    && (alias.child().pushableOptions() == Expression.PushableOptions.PREFERRED)) {
+                        pushableExpressions.put(alias.id(), alias);
+                    }
             });
             AttributeMap<Attribute> aliasReplacedBy = aliasReplacedByBuilder.build();