Document sub-second precision support in MySQL

2 files changed, 72 insertions, 0 deletions

diff --git a/NEWS b/NEWS
index 225a38a..720834c 100644
--- a/NEWS
+++ b/NEWS
@@ -27,6 +27,14 @@ Version 2.3.0
    to the ODB compiler command line interface documentation (man pages) for
    details.
 
+ * Starting with MySQL version 5.6.4 it is possible to store fractional
+   seconds up to microsecond precision in TIME, DATETIME, and TIMESTAMP
+   columns. Both Boost and Qt profiles have been updated to support this
+   new functionality. Note, however, that to enable sub-second precision,
+   the corresponding type with the desired precision has to be specified
+   explicitly. For details, refer to the "MySQL Database Type Mapping"
+   sections in the Boost and Qt profile chapters.
+
  * New SQLite-specific exception, odb::sqlite::forced_rollback, which is
    thrown if SQLite forces a transaction to roll back. For more information,
    refer to Section 16.5.6, "Forced Rollback" in the ODB manual.
diff --git a/doc/manual.xhtml b/doc/manual.xhtml
index c879248..2746a0c 100644
--- a/doc/manual.xhtml
+++ b/doc/manual.xhtml
@@ -20264,6 +20264,38 @@ class person
 };
   </pre>
 
+  <p>Starting with MySQL version 5.6.4 it is possible to store fractional
+     seconds up to microsecond precision in <code>TIME</code>,
+     <code>DATETIME</code>, and <code>TIMESTAMP</code> columns. However,
+     to enable sub-second precision, the corresponding type with the
+     desired precision has to be specified explicitly, as shown in the
+     following example:</p>
+
+  <pre class="cxx">
+#pragma db object
+class person
+{
+  ...
+  #pragma db type("DATETIME(6)")     // Microsecond precision.
+  boost::posix_time::ptime updated_;
+};
+  </pre>
+
+  <p>Alternatively, you can enable sub-second precision on the per-type
+     basis, for example:</p>
+
+  <pre class="cxx">
+#pragma db value(boost::posix_time::ptime) type("DATETIME(6)")
+
+#pragma db object
+class person
+{
+  ...
+  boost::posix_time::ptime created_; // Microsecond precision.
+  boost::posix_time::ptime updated_; // Microsecond precision.
+};
+  </pre>
+
   <p>Some valid Boost date-time values cannot be stored in a MySQL database.
      An attempt to persist any Boost date-time special value other than
      <code>date_time::not_a_date_time</code> will result in the
@@ -21414,6 +21446,38 @@ class Person
 };
   </pre>
 
+  <p>Starting with MySQL version 5.6.4 it is possible to store fractional
+     seconds up to microsecond precision in <code>TIME</code>,
+     <code>DATETIME</code>, and <code>TIMESTAMP</code> columns. However,
+     to enable sub-second precision, the corresponding type with the
+     desired precision has to be specified explicitly, as shown in the
+     following example:</p>
+
+  <pre class="cxx">
+#pragma db object
+class Person
+{
+  ...
+  #pragma db type("DATETIME(3)") // Millisecond precision.
+  QDateTime updated_;
+};
+  </pre>
+
+  <p>Alternatively, you can enable sub-second precision on the per-type
+     basis, for example:</p>
+
+  <pre class="cxx">
+#pragma db value(QDateTime) type("DATETIME(3)")
+
+#pragma db object
+class Person
+{
+  ...
+  QDateTime created_; // Millisecond precision.
+  QDateTime updated_; // Millisecond precision.
+};
+  </pre>
+
   <p>Some valid Qt date-time values cannot be stored in a MySQL database.  An
      attempt to persist a Qt date-time value that is out of the MySQL type
      range will result in the <code>out_of_range</code> exception.  Refer to