path: root/doc/manual.xhtml
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authorBoris Kolpackov <boris@codesynthesis.com>2014-09-19 14:35:46 +0200
committerBoris Kolpackov <boris@codesynthesis.com>2014-09-19 14:35:46 +0200
commitef27013bab8ce027cce1c3efe4acafb8aef9d2e3 (patch)
treefd697936987a832d86c52a12e5583af4bbba1968 /doc/manual.xhtml
parentbba30281f89fbd30e898071a103643be924f001d (diff)
Add stderr_full_tracer that additionally traces statement preparation
Diffstat (limited to 'doc/manual.xhtml')
1 files changed, 10 insertions, 3 deletions
diff --git a/doc/manual.xhtml b/doc/manual.xhtml
index 6a12f57..13203f0 100644
--- a/doc/manual.xhtml
+++ b/doc/manual.xhtml
@@ -4139,9 +4139,16 @@ t.commit ();
<p>The <code>odb::tracer</code> class defines a callback interface
that can be used to create custom tracer implementations. The
- <code>odb::stderr_tracer</code> is a built-in tracer implementation
- provided by the ODB runtime. It prints each executed SQL statement
- to the standard error stream.</p>
+ <code>odb::stderr_tracer</code> and <code>odb::stderr_full_tracer</code>
+ are built-in tracer implementations provided by the ODB runtime.
+ They both print SQL statements being executed to the standard error
+ stream. The full tracer, in addition to tracing statement executions,
+ also traces their preparations and deallocations. One situation where
+ the full tracer can be particularly useful is if a statement (for
+ example a custom query) contains a syntax error. In this case the
+ error will be detected during preparation and, as a result, the
+ statement will never be executed. The only way to see such a statement
+ is by using the full tracing.</p>
<p>The <code>odb::tracer</code> class is defined in the
<code>&lt;odb/tracer.hxx></code> header file which you will need to