### Description

This is to investigate what we could do to support the data streams in SQL. The backing indices can be queried already, but to address them similarly as they're queried over QDSL one would need to construct a pattern learned out of band and not through SQL metadata discovery mechanisms.
x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/index/IndexResolver.java
}, listener::onFailure));
    }
    private GetAliasesRequest createGetAliasesRequest(FieldCapabilitiesResponse response, boolean includeFrozen) {
        return new GetAliasesRequest().local(true)
            .aliases("*")
            .indices(response.getIndices())
            .indicesOptions(includeFrozen ? FIELD_CAPS_FROZEN_INDICES_OPTIONS : FIELD_CAPS_INDICES_OPTIONS);
    }
    public static List<EsIndex> separateMappings(
        DataTypeRegistry typeRegistry,
        String javaRegex,
        FieldCapabilitiesResponse fieldCaps,
        ImmutableOpenMap<String, List<AliasMetadata>> aliases
    ) {
        return buildIndices(typeRegistry, javaRegex, fieldCaps, aliases, Function.identity(), (s, cap) -> null);
    }
    private static class Fields {
        final Map<String, EsField> hierarchicalMapping = new TreeMap<>();
        final Map<String, EsField> flattedMapping = new LinkedHashMap<>();
    }
    /**
     * Assemble an index-based mapping from the field caps (which is field based) by looking at the indices associated with
     * each field.
     */
    private static List<EsIndex> buildIndices(
        DataTypeRegistry typeRegistry,
        String javaRegex,
        FieldCapabilitiesResponse fieldCapsResponse,
        ImmutableOpenMap<String, List<AliasMetadata>> aliases,
        Function<String, String> indexNameProcessor,