Index: art/syntax/bubble-generator-data.tcl
==================================================================
--- art/syntax/bubble-generator-data.tcl
+++ art/syntax/bubble-generator-data.tcl
@@ -488,11 +488,11 @@
   qualified-table-name {
      line {optx /schema-name .} /table-name
           {or nil {line INDEXED BY /index-name} {line NOT INDEXED}}
   }
   vacuum-stmt {
-      line VACUUM
+      line VACUUM {optx /schema-name}
   }
   comment-syntax {
     or
       {line -- {loop nil /anything-except-newline} 
            {or /newline /end-of-input}}

Index: art/syntax/vacuum-stmt.gif
==================================================================
--- art/syntax/vacuum-stmt.gif
+++ art/syntax/vacuum-stmt.gif
cannot compute difference between binary files

Index: pages/lang.in
==================================================================
--- pages/lang.in
+++ pages/lang.in
@@ -4516,11 +4516,12 @@
 
 RecursiveBubbleDiagram vacuum-stmt
 </tcl>
 
 <p>
-  The VACUUM command rebuilds the entire database. There are several 
+  The VACUUM command rebuilds an entire database, packing the content as
+  tightly as possible. There are several 
   reasons an application might do this:
 
 <ul>
   <li> <p> ^Unless SQLite is running in "auto_vacuum=FULL" mode, when a large
      amount of data is deleted from the database file it leaves behind empty
@@ -4543,12 +4544,19 @@
      [auto_vacuum|pragma auto_vacuum] pragmas and then immediately VACUUMing
      the database. ^When in [write-ahead log] mode, only the [auto_vacuum]
      support property can be changed using VACUUM.
 </ul>
 
-<p>^(VACUUM only works on the main database. It is not possible to VACUUM an
-attached database file.)^
+<p>On all versions of SQLite through [version 3.14.1], 
+the VACUUM command only worked on the main database schema.  
+The optional <yyterm>schema-name</yyterm> argument was
+accepted by silently ignored.  Beginning with SQLite [version 3.15.0],
+any database other than TEMP can be vacuumed by providing its
+<yyterm>schema-name</yyterm> as an argument.  If the argument is
+omitted, the default is "main".  The schema-name argument is the
+name following the AS keyword in the [ATTACH] statement, not the
+name of the database file.
 
 <p>^The VACUUM command works by copying the contents of the database into
 a temporary database file and then overwriting the original with the 
 contents of the temporary file. ^When overwriting the original, a rollback
 journal or [write-ahead log] WAL file is used just as it would be for any
@@ -4558,23 +4566,31 @@
 
 <p>^The VACUUM command may change the [ROWID | ROWIDs] of entries in any
 tables that do not have an explicit [INTEGER PRIMARY KEY].
 </p>
 
-<p>^A VACUUM will fail if there is an open transaction, or if there are one or
-more active SQL statements when it is run.
 
 <p>^(As of SQLite version 3.1, an alternative to using the VACUUM command to
 reclaim space after data has been deleted is auto-vacuum mode, enabled using
 the [auto_vacuum] pragma.)^ ^When [auto_vacuum] is enabled for a database
 free pages may be reclaimed after deleting data, causing the file to shrink,
 without rebuilding the entire database using VACUUM.  However, using
 [auto_vacuum] can lead to extra database file fragmentation.  And [auto_vacuum]
 does not compact partially filled pages of the database as VACUUM does.
-
 </p>
 
+<h3>Restrictions</h3>
+
+<p>^A VACUUM will fail if there is an open transaction, or if there are one or
+more active SQL statements when it is run.
+
+<p>^The VACUUM command will fail with an obscure error if the
+[database connection] contains any [ATTACH]-ed database whose
+schema-name is "vacuum_db".  This is due to the fact that the
+VACUUM command [ATTACH]-es a temporary table named "vacuum_db"
+as part of its processing.
+
 
 <tcl>
 ##############################################################################
 Section {INDEXED BY} indexedby {{INDEXED BY} {NOT INDEXED}}