diff --git a/reference/mysqli/functions/mysqli-get-client-stats.xml b/reference/mysqli/functions/mysqli-get-client-stats.xml
index b2dbcc5c2fd8..64061127353d 100644
--- a/reference/mysqli/functions/mysqli-get-client-stats.xml
+++ b/reference/mysqli/functions/mysqli-get-client-stats.xml
@@ -9,8 +9,8 @@
  <refsect1 role="description">
   &reftitle.description;
   <methodsynopsis>
-   <type>array</type><methodname>mysqli_get_client_stats</methodname>
-   <void/>
+   <type class="union"><type>array</type><type>false</type></type><methodname>mysqli_get_client_stats</methodname>
+   <void />
   </methodsynopsis>
   <para>
    Returns client per-process statistics.
diff --git a/reference/mysqli/mysqli/construct.xml b/reference/mysqli/mysqli/construct.xml
index 6e2fa27c2db2..2ecb75804a2c 100644
--- a/reference/mysqli/mysqli/construct.xml
+++ b/reference/mysqli/mysqli/construct.xml
@@ -21,7 +21,7 @@
    <methodparam choice="opt"><type>string</type><parameter>socket</parameter><initializer>ini_get("mysqli.default_socket")</initializer></methodparam>
   </constructorsynopsis>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>void</type><methodname>mysqli::connect</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli</type><type>false</type></type><methodname>mysqli::connect</methodname>
    <methodparam choice="opt"><type>string</type><parameter>host</parameter><initializer>ini_get("mysqli.default_host")</initializer></methodparam>
    <methodparam choice="opt"><type>string</type><parameter>username</parameter><initializer>ini_get("mysqli.default_user")</initializer></methodparam>
    <methodparam choice="opt"><type>string</type><parameter>passwd</parameter><initializer>ini_get("mysqli.default_pw")</initializer></methodparam>
diff --git a/reference/mysqli/mysqli/get-connection-stats.xml b/reference/mysqli/mysqli/get-connection-stats.xml
index a5abec0e75a8..bbb2d081386e 100644
--- a/reference/mysqli/mysqli/get-connection-stats.xml
+++ b/reference/mysqli/mysqli/get-connection-stats.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>bool</type><methodname>mysqli::get_connection_stats</methodname>
-   <void/>
+   <modifier>public</modifier> <type class="union"><type>array</type><type>false</type></type><methodname>mysqli::get_connection_stats</methodname>
+   <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>array</type><methodname>mysqli_get_connection_stats</methodname>
+   <type class="union"><type>array</type><type>false</type></type><methodname>mysqli_get_connection_stats</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli/insert-id.xml b/reference/mysqli/mysqli/insert-id.xml
index bb5f7d1af5c4..09ccf3e07f75 100644
--- a/reference/mysqli/mysqli/insert-id.xml
+++ b/reference/mysqli/mysqli/insert-id.xml
@@ -13,7 +13,7 @@
   <fieldsynopsis><type>mixed</type><varname linkend="mysqli.insert-id">mysqli->insert_id</varname></fieldsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mixed</type><methodname>mysqli_insert_id</methodname>
+   <type class="union"><type>int</type><type>string</type></type><methodname>mysqli_insert_id</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli/poll.xml b/reference/mysqli/mysqli/poll.xml
index 020a94b9b868..3936e7eda335 100644
--- a/reference/mysqli/mysqli/poll.xml
+++ b/reference/mysqli/mysqli/poll.xml
@@ -11,7 +11,7 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <modifier>static</modifier> <type>int</type><methodname>mysqli::poll</methodname>
+   <modifier>public</modifier> <modifier>static</modifier> <type class="union"><type>int</type><type>false</type></type><methodname>mysqli::poll</methodname>
    <methodparam><type>array</type><parameter role="reference">read</parameter></methodparam>
    <methodparam><type>array</type><parameter role="reference">error</parameter></methodparam>
    <methodparam><type>array</type><parameter role="reference">reject</parameter></methodparam>
@@ -20,7 +20,7 @@
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>int</type><methodname>mysqli_poll</methodname>
+   <type class="union"><type>int</type><type>false</type></type><methodname>mysqli_poll</methodname>
    <methodparam><type>array</type><parameter role="reference">read</parameter></methodparam>
    <methodparam><type>array</type><parameter role="reference">error</parameter></methodparam>
    <methodparam><type>array</type><parameter role="reference">reject</parameter></methodparam>
diff --git a/reference/mysqli/mysqli/prepare.xml b/reference/mysqli/mysqli/prepare.xml
index 62806d2dc5bf..6926b6e039c8 100644
--- a/reference/mysqli/mysqli/prepare.xml
+++ b/reference/mysqli/mysqli/prepare.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mysqli_stmt</type><methodname>mysqli::prepare</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli_stmt</type><type>false</type></type><methodname>mysqli::prepare</methodname>
    <methodparam><type>string</type><parameter>query</parameter></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mysqli_stmt</type><methodname>mysqli_prepare</methodname>
+   <type class="union"><type>mysqli_stmt</type><type>false</type></type><methodname>mysqli_prepare</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
    <methodparam><type>string</type><parameter>query</parameter></methodparam>
   </methodsynopsis>
diff --git a/reference/mysqli/mysqli/query.xml b/reference/mysqli/mysqli/query.xml
index d772d70cfef0..2a56ee8c8e02 100644
--- a/reference/mysqli/mysqli/query.xml
+++ b/reference/mysqli/mysqli/query.xml
@@ -11,13 +11,13 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mixed</type><methodname>mysqli::query</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli_result</type><type>bool</type></type><methodname>mysqli::query</methodname>
    <methodparam><type>string</type><parameter>query</parameter></methodparam>
    <methodparam choice="opt"><type>int</type><parameter>resultmode</parameter><initializer>MYSQLI_STORE_RESULT</initializer></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mixed</type><methodname>mysqli_query</methodname>
+   <type class="union"><type>mysqli_result</type><type>bool</type></type><methodname>mysqli_query</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
    <methodparam><type>string</type><parameter>query</parameter></methodparam>
    <methodparam choice="opt"><type>int</type><parameter>resultmode</parameter><initializer>MYSQLI_STORE_RESULT</initializer></methodparam>
diff --git a/reference/mysqli/mysqli/reap-async-query.xml b/reference/mysqli/mysqli/reap-async-query.xml
index e05a6d6707e3..dcbad66919b3 100644
--- a/reference/mysqli/mysqli/reap-async-query.xml
+++ b/reference/mysqli/mysqli/reap-async-query.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mysqli_result</type><methodname>mysqli::reap_async_query</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli::reap_async_query</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mysqli_result</type><methodname>mysqli_reap_async_query</methodname>
+   <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli_reap_async_query</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli/stat.xml b/reference/mysqli/mysqli/stat.xml
index a1c2e8eaa54a..7288e5ecfa7f 100644
--- a/reference/mysqli/mysqli/stat.xml
+++ b/reference/mysqli/mysqli/stat.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>string</type><methodname>mysqli::stat</methodname>
+   <modifier>public</modifier> <type class="union"><type>string</type><type>false</type></type><methodname>mysqli::stat</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>string</type><methodname>mysqli_stat</methodname>
+   <type class="union"><type>string</type><type>false</type></type><methodname>mysqli_stat</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli/store-result.xml b/reference/mysqli/mysqli/store-result.xml
index a3457c183c9b..05c97fc8a142 100644
--- a/reference/mysqli/mysqli/store-result.xml
+++ b/reference/mysqli/mysqli/store-result.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mysqli_result</type><methodname>mysqli::store_result</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli::store_result</methodname>
    <methodparam choice="opt"><type>int</type><parameter>option</parameter></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mysqli_result</type><methodname>mysqli_store_result</methodname>
+   <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli_store_result</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
    <methodparam choice="opt"><type>int</type><parameter>option</parameter></methodparam>
   </methodsynopsis>
diff --git a/reference/mysqli/mysqli/use-result.xml b/reference/mysqli/mysqli/use-result.xml
index bb51eaff8030..aa1479249994 100644
--- a/reference/mysqli/mysqli/use-result.xml
+++ b/reference/mysqli/mysqli/use-result.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mysqli_result</type><methodname>mysqli::use_result</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli::use_result</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mysqli_result</type><methodname>mysqli_use_result</methodname>
+   <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli_use_result</methodname>
    <methodparam><type>mysqli</type><parameter>link</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_result/fetch-all.xml b/reference/mysqli/mysqli_result/fetch-all.xml
index 0eddf88dcb5b..860428985be8 100644
--- a/reference/mysqli/mysqli_result/fetch-all.xml
+++ b/reference/mysqli/mysqli_result/fetch-all.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mixed</type><methodname>mysqli_result::fetch_all</methodname>
+   <modifier>public</modifier> <type>array</type><methodname>mysqli_result::fetch_all</methodname>
    <methodparam choice="opt"><type>int</type><parameter>resulttype</parameter><initializer>MYSQLI_NUM</initializer></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mixed</type><methodname>mysqli_fetch_all</methodname>
+   <type>array</type><methodname>mysqli_fetch_all</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
    <methodparam choice="opt"><type>int</type><parameter>resulttype</parameter><initializer>MYSQLI_NUM</initializer></methodparam>
   </methodsynopsis>
diff --git a/reference/mysqli/mysqli_result/fetch-array.xml b/reference/mysqli/mysqli_result/fetch-array.xml
index 993a7962482c..0f3c3b2bb639 100644
--- a/reference/mysqli/mysqli_result/fetch-array.xml
+++ b/reference/mysqli/mysqli_result/fetch-array.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mixed</type><methodname>mysqli_result::fetch_array</methodname>
+   <modifier>public</modifier> <type class="union"><type>array</type><type>null</type></type><methodname>mysqli_result::fetch_array</methodname>
    <methodparam choice="opt"><type>int</type><parameter>resulttype</parameter><initializer>MYSQLI_BOTH</initializer></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mixed</type><methodname>mysqli_fetch_array</methodname>
+   <type class="union"><type>array</type><type>null</type></type><methodname>mysqli_fetch_array</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
    <methodparam choice="opt"><type>int</type><parameter>resulttype</parameter><initializer>MYSQLI_BOTH</initializer></methodparam>
   </methodsynopsis>
diff --git a/reference/mysqli/mysqli_result/fetch-assoc.xml b/reference/mysqli/mysqli_result/fetch-assoc.xml
index 4fb4aca3c48a..836fb812557c 100644
--- a/reference/mysqli/mysqli_result/fetch-assoc.xml
+++ b/reference/mysqli/mysqli_result/fetch-assoc.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>array</type><methodname>mysqli_result::fetch_assoc</methodname>
+   <modifier>public</modifier> <type class="union"><type>string[]</type><type>null</type></type><methodname>mysqli_result::fetch_assoc</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>array</type><methodname>mysqli_fetch_assoc</methodname>
+   <type class="union"><type>string[]</type><type>null</type></type><methodname>mysqli_fetch_assoc</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_result/fetch-field-direct.xml b/reference/mysqli/mysqli_result/fetch-field-direct.xml
index 665cc3b26a6a..c1a08c96f294 100644
--- a/reference/mysqli/mysqli_result/fetch-field-direct.xml
+++ b/reference/mysqli/mysqli_result/fetch-field-direct.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>object</type><methodname>mysqli_result::fetch_field_direct</methodname>
+   <modifier>public</modifier> <type class="union"><type>object</type><type>false</type></type><methodname>mysqli_result::fetch_field_direct</methodname>
    <methodparam><type>int</type><parameter>fieldnr</parameter></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>object</type><methodname>mysqli_fetch_field_direct</methodname>
+   <type class="union"><type>object</type><type>false</type></type><methodname>mysqli_fetch_field_direct</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
    <methodparam><type>int</type><parameter>fieldnr</parameter></methodparam>
   </methodsynopsis>
diff --git a/reference/mysqli/mysqli_result/fetch-field.xml b/reference/mysqli/mysqli_result/fetch-field.xml
index f34f90e0cb80..27aa32f54c94 100644
--- a/reference/mysqli/mysqli_result/fetch-field.xml
+++ b/reference/mysqli/mysqli_result/fetch-field.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>object</type><methodname>mysqli_result::fetch_field</methodname>
-   <void/>
+   <modifier>public</modifier> <type class="union"><type>object</type><type>false</type></type><methodname>mysqli_result::fetch_field</methodname>
+   <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>object</type><methodname>mysqli_fetch_field</methodname>
+   <type class="union"><type>object</type><type>false</type></type><methodname>mysqli_fetch_field</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_result/fetch-fields.xml b/reference/mysqli/mysqli_result/fetch-fields.xml
index 5de91e1ee1ac..a8d49df8b2a7 100644
--- a/reference/mysqli/mysqli_result/fetch-fields.xml
+++ b/reference/mysqli/mysqli_result/fetch-fields.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>array</type><methodname>mysqli_result::fetch_fields</methodname>
-   <void/>
+   <modifier>public</modifier> <type class="union"><type>array</type><type>false</type></type><methodname>mysqli_result::fetch_fields</methodname>
+   <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>array</type><methodname>mysqli_fetch_fields</methodname>
+   <type class="union"><type>array</type><type>false</type></type><methodname>mysqli_fetch_fields</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
   </methodsynopsis>
 
diff --git a/reference/mysqli/mysqli_result/fetch-object.xml b/reference/mysqli/mysqli_result/fetch-object.xml
index 8bae4d918a60..e6c10bd8e547 100644
--- a/reference/mysqli/mysqli_result/fetch-object.xml
+++ b/reference/mysqli/mysqli_result/fetch-object.xml
@@ -11,13 +11,13 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>object</type><methodname>mysqli_result::fetch_object</methodname>
+   <modifier>public</modifier> <type class="union"><type>object</type><type>null</type></type><methodname>mysqli_result::fetch_object</methodname>
    <methodparam choice="opt"><type>string</type><parameter>class_name</parameter><initializer>"stdClass"</initializer></methodparam>
    <methodparam choice="opt"><type>array</type><parameter>params</parameter></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>object</type><methodname>mysqli_fetch_object</methodname>
+   <type class="union"><type>object</type><type>null</type></type><methodname>mysqli_fetch_object</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
    <methodparam choice="opt"><type>string</type><parameter>class_name</parameter><initializer>"stdClass"</initializer></methodparam>
    <methodparam choice="opt"><type>array</type><parameter>params</parameter></methodparam>
diff --git a/reference/mysqli/mysqli_result/fetch-row.xml b/reference/mysqli/mysqli_result/fetch-row.xml
index dd9535af676b..b39884a0e299 100644
--- a/reference/mysqli/mysqli_result/fetch-row.xml
+++ b/reference/mysqli/mysqli_result/fetch-row.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mixed</type><methodname>mysqli_result::fetch_row</methodname>
+   <modifier>public</modifier> <type class="union"><type>array</type><type>null</type></type><methodname>mysqli_result::fetch_row</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mixed</type><methodname>mysqli_fetch_row</methodname>
+   <type class="union"><type>array</type><type>null</type></type><methodname>mysqli_fetch_row</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_result/lengths.xml b/reference/mysqli/mysqli_result/lengths.xml
index 7ce01522b10f..d8274dd6e89c 100644
--- a/reference/mysqli/mysqli_result/lengths.xml
+++ b/reference/mysqli/mysqli_result/lengths.xml
@@ -13,7 +13,7 @@
   <fieldsynopsis><type>array</type><varname linkend="mysqli-result.lengths">mysqli_result->lengths</varname></fieldsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>array</type><methodname>mysqli_fetch_lengths</methodname>
+   <type class="union"><type>int[]</type><type>false</type></type><methodname>mysqli_fetch_lengths</methodname>
    <methodparam><type>mysqli_result</type><parameter>result</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_stmt/affected-rows.xml b/reference/mysqli/mysqli_stmt/affected-rows.xml
index d317e82f43d6..a6c53a318321 100644
--- a/reference/mysqli/mysqli_stmt/affected-rows.xml
+++ b/reference/mysqli/mysqli_stmt/affected-rows.xml
@@ -15,7 +15,7 @@
   <fieldsynopsis><type>int</type><varname linkend="mysqli-stmt.affected-rows">mysqli_stmt->affected_rows</varname></fieldsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>int</type><methodname>mysqli_stmt_affected_rows</methodname>
+   <type class="union"><type>int</type><type>string</type></type><methodname>mysqli_stmt_affected_rows</methodname>
    <methodparam><type>mysqli_stmt</type><parameter>stmt</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_stmt/attr-get.xml b/reference/mysqli/mysqli_stmt/attr-get.xml
index 383d1fb1c01c..f48d48c468c1 100644
--- a/reference/mysqli/mysqli_stmt/attr-get.xml
+++ b/reference/mysqli/mysqli_stmt/attr-get.xml
@@ -12,12 +12,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>int</type><methodname>mysqli_stmt::attr_get</methodname>
+   <modifier>public</modifier> <type class="union"><type>int</type><type>false</type></type><methodname>mysqli_stmt::attr_get</methodname>
    <methodparam><type>int</type><parameter>attr</parameter></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>int</type><methodname>mysqli_stmt_attr_get</methodname>
+   <type class="union"><type>int</type><type>false</type></type><methodname>mysqli_stmt_attr_get</methodname>
    <methodparam><type>mysqli_stmt</type><parameter>stmt</parameter></methodparam>
    <methodparam><type>int</type><parameter>attr</parameter></methodparam>
   </methodsynopsis>
diff --git a/reference/mysqli/mysqli_stmt/fetch.xml b/reference/mysqli/mysqli_stmt/fetch.xml
index ba0da3cc6295..d998cc2bdbdc 100644
--- a/reference/mysqli/mysqli_stmt/fetch.xml
+++ b/reference/mysqli/mysqli_stmt/fetch.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>bool</type><methodname>mysqli_stmt::fetch</methodname>
+   <modifier>public</modifier> <type class="union"><type>bool</type><type>null</type></type><methodname>mysqli_stmt::fetch</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>bool</type><methodname>mysqli_stmt_fetch</methodname>
+   <type class="union"><type>bool</type><type>null</type></type><methodname>mysqli_stmt_fetch</methodname>
    <methodparam><type>mysqli_stmt</type><parameter>stmt</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_stmt/get-result.xml b/reference/mysqli/mysqli_stmt/get-result.xml
index 14a35921298b..d67ae9ff2631 100644
--- a/reference/mysqli/mysqli_stmt/get-result.xml
+++ b/reference/mysqli/mysqli_stmt/get-result.xml
@@ -12,12 +12,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mysqli_result</type><methodname>mysqli_stmt::get_result</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli_stmt::get_result</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mysqli_result</type><methodname>mysqli_stmt_get_result</methodname>
+   <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli_stmt_get_result</methodname>
    <methodparam><type>mysqli_stmt</type><parameter>stmt</parameter></methodparam>
   </methodsynopsis>
   <para>
diff --git a/reference/mysqli/mysqli_stmt/prepare.xml b/reference/mysqli/mysqli_stmt/prepare.xml
index 4c2d49e6cd06..2cc8e497fba1 100644
--- a/reference/mysqli/mysqli_stmt/prepare.xml
+++ b/reference/mysqli/mysqli_stmt/prepare.xml
@@ -11,7 +11,7 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mixed</type><methodname>mysqli_stmt::prepare</methodname>
+   <modifier>public</modifier> <type>bool</type><methodname>mysqli_stmt::prepare</methodname>
    <methodparam><type>string</type><parameter>query</parameter></methodparam>
   </methodsynopsis>
   <para>&style.procedural;</para>
diff --git a/reference/mysqli/mysqli_stmt/result-metadata.xml b/reference/mysqli/mysqli_stmt/result-metadata.xml
index dc23b9a09b74..4fa123645a5c 100644
--- a/reference/mysqli/mysqli_stmt/result-metadata.xml
+++ b/reference/mysqli/mysqli_stmt/result-metadata.xml
@@ -11,12 +11,12 @@
   &reftitle.description;
   <para>&style.oop;</para>
   <methodsynopsis role="oop">
-   <modifier>public</modifier> <type>mysqli_result</type><methodname>mysqli_stmt::result_metadata</methodname>
+   <modifier>public</modifier> <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli_stmt::result_metadata</methodname>
    <void />
   </methodsynopsis>
   <para>&style.procedural;</para>
   <methodsynopsis>
-   <type>mysqli_result</type><methodname>mysqli_stmt_result_metadata</methodname>
+   <type class="union"><type>mysqli_result</type><type>false</type></type><methodname>mysqli_stmt_result_metadata</methodname>
    <methodparam><type>mysqli_stmt</type><parameter>stmt</parameter></methodparam>
   </methodsynopsis>
   <para>