Index: include/internal/chewing-private.h
===================================================================
--- include/internal/chewing-private.h	(revision 885)
+++ include/internal/chewing-private.h	(working copy)
@@ -42,6 +42,9 @@ typedef struct {
 	uint16 phone_id;
 	int phrase_id;
 	int child_begin, child_end;
+//#ifdef USE_BINARY_DATA_SQLITE
+	int fetched;
+//#endif
 } TreeType;
 
 typedef struct {
Index: include/internal/global-private.h
===================================================================
--- include/internal/global-private.h	(revision 885)
+++ include/internal/global-private.h	(working copy)
@@ -13,6 +13,12 @@
 #ifndef _CHEWING_GLOBAL_PRIVATE_H
 #define _CHEWING_GLOBAL_PRIVATE_H
 
+#ifdef HAVE_CONFIG_H
+#ifndef PACKAGE_NAME
+#include "config.h"
+#endif
+#endif
+
 #define PHONE_TREE_FILE		"fonetree.dat"
 #define DICT_FILE		"dict.dat"
 #define PH_INDEX_FILE		"ph_index.dat"
Index: src/tree.c
===================================================================
--- src/tree.c	(revision 885)
+++ src/tree.c	(working copy)
@@ -31,6 +31,10 @@
 #include "private.h"
 #include "plat_mmap.h"
 
+#ifdef USE_BINARY_DATA_SQLITE
+#include <sqlite3.h>
+#endif
+
 #define INTERVAL_SIZE ( ( MAX_PHONE_SEQ_LEN + 1 ) * MAX_PHONE_SEQ_LEN / 2 )
 
 typedef struct {
@@ -55,10 +59,14 @@ typedef struct {
 } TreeDataType;
 
 #ifdef USE_BINARY_DATA
-extern TreeType *tree;
+TreeType *tree;
 static unsigned int tree_size = 0;
-#else
-extern TreeType tree[ TREE_SIZE ];
+#ifdef USE_BINARY_DATA_SQLITE
+static sqlite3 *db = NULL;
+static sqlite3_stmt *stFetch;
+#endif
+#else /* ! USE_BINARY_DATA */
+TreeType tree[ TREE_SIZE ];
 #endif
 
 static int IsContain( IntervalType in1, IntervalType in2 )
@@ -98,6 +106,10 @@ static void TerminateTree()
 #ifdef USE_BINARY_DATA
 	if ( tree )
 		free( tree );
+#ifdef USE_BINARY_DATA_SQLITE
+	if ( stFetch )
+		sqlite3_finalize( stFetch );
+#endif
 #endif
 }
 
@@ -106,15 +118,52 @@ void ReadTree( const char *prefix )
 	char filename[ 100 ];
 
 #ifdef USE_BINARY_DATA
+#ifdef USE_BINARY_DATA_SQLITE
+	int rc;
+	sqlite3_stmt *st;
+	char *buf;
+#else /* ! USE_BINARY_DATA_SQLITE */
 	int infile;
 	struct stat file_stat;
-#else
+#endif
+#else /* ! USE_BINARY_DATA */
 	FILE *infile;
 	int i;
 #endif
 
 	sprintf( filename, "%s" PLAT_SEPARATOR "%s", prefix, PHONE_TREE_FILE );
 #ifdef USE_BINARY_DATA
+#ifdef USE_BINARY_DATA_SQLITE
+        rc = sqlite3_open( filename, &db );
+        if ( rc ) {
+		DEBUG_OUT( "Can't open database: %s\n",
+		           sqlite3_errmsg( db ) );
+                sqlite3_close( db );
+		/* FIXME: exception handling with database */
+		return;
+        }
+        rc = sqlite3_prepare( db,
+	"SELECT id,phone_id,phrase_id,child_begin,child_end FROM tree WHERE id = ?",
+	                      -1 , &stFetch,
+	                      (const char **) &buf);
+        if ( rc != SQLITE_OK ) {
+		DEBUG_OUT( "SQL error (prepare SELECT): %d\n", rc );
+	}
+
+        rc = sqlite3_prepare( db,
+	"SELECT max(id) FROM tree" ,
+	                      -1 ,
+	                      &st , (const char **) &buf);
+        rc = sqlite3_step( st );
+        if ( rc != SQLITE_ROW ) {
+		DEBUG_OUT( "SQL error: %d\n", rc );
+	}
+        tree_size = sqlite3_column_int( st, 0 ) + 1;
+        tree = ALC( TreeType, tree_size );
+	memset( tree, 0, tree_size * sizeof(TreeType) );
+
+        sqlite3_finalize( st );
+#else 	/* ! USE_BINARY_DATA_SQLITE */
 	infile = open( filename, O_RDONLY );
 
 	if ( infile == -1  )
@@ -127,7 +176,8 @@ void ReadTree( const char *prefix )
 		read( infile, tree, tree_size );
 
 	close( infile );
-#else
+#endif
+#else 	/* ! USE_BINARY_DATA */
 	infile = fopen( filename, "r" );
 	assert( infile );
 	for ( i = 0; i < TREE_SIZE; i++ ) {
@@ -276,6 +326,23 @@ static int CheckChoose(
 	return 0;
 }
 
+#ifdef USE_BINARY_DATA_SQLITE
+static int TreeFetchNode( int id )
+{
+	if ( ! tree[ id ].fetched ) {
+		sqlite3_reset( stFetch );
+		sqlite3_bind_int( stFetch, 1, id );
+		sqlite3_step( stFetch );
+
+		tree[ id ].phone_id = sqlite3_column_int( stFetch, 1 );
+		tree[ id ].phrase_id = sqlite3_column_int( stFetch, 2 );
+		tree[ id ].child_begin = sqlite3_column_int( stFetch, 3 );
+		tree[ id ].child_end = sqlite3_column_int( stFetch, 4 );
+		tree[ id ].fetched = 1;
+	}
+}
+#endif
+
 /** @brief search for the phrases have the same pronunciation.*/
 /* if phoneSeq[a] ~ phoneSeq[b] is a phrase, then add an interval
  * from (a) to (b+1) */
@@ -285,6 +352,9 @@ int TreeFindPhrase( int begin, int end, 
 
 	tree_p = 0;
 	for ( i = begin; i <= end; i++ ) {
+#ifdef USE_BINARY_DATA_SQLITE
+		TreeFetchNode( tree_p );
+#endif
 		for ( 
 			child = tree[ tree_p ].child_begin;
 			child <= tree[ tree_p ].child_end;
@@ -299,8 +369,13 @@ int TreeFindPhrase( int begin, int end, 
 			 */
 			if ( child < 0 || child * sizeof(TreeType) > tree_size )
 				return -1;
+#elif defined(USE_BINARY_DATA_SQLITE)
+			if ( child == -1 )
+				continue;
+			if ( child * sizeof(TreeType) > tree_size )
+				return -1;
+			TreeFetchNode( child );
 #endif
-
 			if ( tree[ child ].phone_id == phoneSeq[ i ] )
 				break;
 		}
Index: src/tools/dat2bin.c
===================================================================
--- src/tools/dat2bin.c	(revision 885)
+++ src/tools/dat2bin.c	(working copy)
@@ -36,7 +36,9 @@
 #define USED_IN_DAT2BIN
 #include "sort_word.c"
 #include "sort_dic.c"
+#ifndef USE_BINARY_DATA_SQLITE
 #include "maketree.c"
+#endif
 #undef USED_IN_DAT2BIN
 
 int main( int argc, char* argv[] )
@@ -56,8 +58,10 @@ int main( int argc, char* argv[] )
 	printf("sort_dic...\n");
 	sort_dic();
 
+#ifndef USE_BINARY_DATA_SQLITE
 	printf("maketree...\n");
 	maketree();
+#endif
 
 	printf("sort_word...\n");
 	sort_word();
@@ -91,6 +95,9 @@ int main( int argc, char* argv[] )
 	}
 	fclose( fi );
 
+#ifdef USE_BINARY_DATA_SQLITE
+	/* Do nothing */
+#else
 	/* PHONE_TREE_FILE */
 	sprintf( filename, "%s" PLAT_SEPARATOR "%s", prefix, PHONE_TREE_FILE );
 	fi = fopen( filename, "r" );
@@ -113,6 +120,7 @@ int main( int argc, char* argv[] )
 		fclose( fo );
 	}
 	fclose( fi );
+#endif
 
 	/* PH_INDEX_FILE */
 	sprintf( filename, "%s" PLAT_SEPARATOR "%s", prefix, PH_INDEX_FILE );
Index: src/tools/Makefile.am
===================================================================
--- src/tools/Makefile.am	(revision 885)
+++ src/tools/Makefile.am	(working copy)
@@ -2,7 +2,8 @@ INCLUDES = \
 	-I$(top_srcdir)/include \
 	-I$(top_srcdir)/include/internal \
 	-I$(top_srcdir)/src \
-	-I$(top_srcdir)/src/porting_layer/include
+	-I$(top_srcdir)/src/porting_layer/include \
+	$(SQLITE3_CFLAGS)
 
 noinst_PROGRAMS = sort_word sort_dic maketree $(DAT2BIN)
 
@@ -19,3 +20,7 @@ sort_dic_LDADD =  $(top_builddir)/src/co
 sort_dic_SOURCES = sort_dic.c
 
 maketree_SOURCES = maketree.c
+
+if ENABLE_BINARY_DATA_SQLITE
+maketree_LDADD = $(SQLITE3_LIBS)
+endif
Index: src/tools/maketree.c
===================================================================
--- src/tools/maketree.c	(revision 885)
+++ src/tools/maketree.c	(working copy)
@@ -5,7 +5,7 @@
  *	Lu-chuan Kung and Kang-pen Chen.
  *	All rights reserved.
  *
- * Copyright (c) 2004
+ * Copyright (c) 2004, 2008
  *	libchewing Core Team. See ChangeLog for details.
  *
  * See the file "COPYING" for information on usage and redistribution
@@ -33,6 +33,9 @@
 #include <assert.h>
 #include "global.h"
 #include "global-private.h"
+#ifdef USE_BINARY_DATA_SQLITE
+#include <sqlite3.h>
+#endif
 
 /*
 	defines
@@ -194,14 +197,61 @@ void BFS2()
 {
 	NODE *pNode;
 	LISTNODE *pList;
-	FILE *output = fopen( PHONE_TREE_FILE, "w" );
-	FILE *config = fopen( CHEWING_DEFINITION_FILE, "aw" );
+	FILE *config;
+#ifdef USE_BINARY_DATA_SQLITE
+	int rc;
+	int i;
+	sqlite3 *db;
+	sqlite3_stmt *st;
+	char *zErrMsg = 0;
+	char *buf;
+
+	rc = sqlite3_open( PHONE_TREE_FILE, &db );
+	if (rc) {
+		fprintf( stderr, "Can't open database: %s\n", sqlite3_errmsg( db ) );
+		sqlite3_close( db );
+		exit( 1 );
+	}
+
+	rc = sqlite3_exec( db,
+	"CREATE TABLE tree (id,phone_id,phrase_id,child_begin,child_end)",
+	                   NULL, NULL, &zErrMsg );
+	if ( rc != SQLITE_OK ) {
+		fprintf( stderr, "A SQL error: %s\n", zErrMsg );
+	}
 
+	rc = sqlite3_exec( db,
+	"CREATE INDEX tree_index ON tree (id)",
+	                   NULL, NULL, &zErrMsg );
+	if ( rc != SQLITE_OK ) {
+		fprintf( stderr, "A SQL error: %s\n", zErrMsg );
+	}
+
+	rc = sqlite3_exec( db,
+	"CREATE INDEX tree_index ON tree (id)",
+	                   NULL, NULL, &zErrMsg );
+	rc = sqlite3_prepare( db,
+	"INSERT INTO tree VALUES (?,?,?,?,?)",
+	                      -1 , &st , (const char **) &buf );
+	if ( rc != SQLITE_OK ) {
+		fprintf( stderr, "B SQL error: %d\n", rc );
+	}
+
+	rc = sqlite3_exec( db,
+	"BEGIN",
+	                   NULL, NULL, &zErrMsg );
+	if ( rc != SQLITE_OK ) {
+		fprintf( stderr, "C SQL error: %s\n", zErrMsg );
+	}
+#else 	/* ! USE_BINARY_DATA_SQLITE */
+	FILE *output = fopen( PHONE_TREE_FILE, "w" );
 	if ( ! output ) {
 		fprintf( stderr, "Error opening file " PHONE_TREE_FILE " for output.\n" );
 		exit( 1 );
 	}
+#endif
 
+	config = fopen( CHEWING_DEFINITION_FILE, "aw" );
 	if ( ! config ) {
 		fprintf( stderr, "Error opening file " CHEWING_DEFINITION_FILE " for output.\n" );
 		exit( 1 );
@@ -209,30 +259,65 @@ void BFS2()
 
 	QueuePut( root );
 	tree_size = 0;
+
+#ifdef USE_BINARY_DATA_SQLITE
+	i = 0;
+#endif
 	while ( ! QueueEmpty() ) {
 		pNode = QueueGet();
-		
+
+#ifdef USE_BINARY_DATA_SQLITE
+		sqlite3_bind_int( st, 1, i++ );
+		sqlite3_bind_int( st, 2, (int) pNode->key );
+		sqlite3_bind_int( st, 3, pNode->phraseno );
+#else 	/* ! USE_BINARY_DATA_SQLITE */
 		fprintf( output, "%hu ", pNode->key );
 		fprintf( output, "%d ", pNode->phraseno );
+#endif
 
 		/* compute the begin and end index */
 		pList = pNode->childList;
-		if( pList ) {
+		if ( pList ) {
+#ifdef USE_BINARY_DATA_SQLITE
+			sqlite3_bind_int( st, 4, pList->pNode->nodeno );
+#else 	/* ! USE_BINARY_DATA_SQLITE */
 			fprintf( output, "%d ", pList->pNode->nodeno );
+#endif
 
 			for ( ; pList->next; pList = pList->next ) {
 				QueuePut( pList->pNode );
 			}
 			QueuePut( pList->pNode );
+#ifdef USE_BINARY_DATA_SQLITE
+			sqlite3_bind_int( st, 5, pList->pNode->nodeno );
+		}
+		else {
+			sqlite3_bind_int( st, 4, -1 );
+			sqlite3_bind_int( st, 5, -1 );
+		}
+#else 	/* ! USE_BINARY_DATA_SQLITE */
 			fprintf( output, "%d\n", pList->pNode->nodeno );
 		}
 		else
 			fprintf( output, "-1 -1\n" );
+#endif
 		tree_size++;
+#ifdef USE_BINARY_DATA_SQLITE
+		sqlite3_step( st );
+		sqlite3_reset( st );
+#endif
 	}
 	fprintf( config, "#define TREE_SIZE (%d)\n", tree_size );
+#ifdef USE_BINARY_DATA_SQLITE
+	rc = sqlite3_exec( db, "COMMIT", NULL, NULL, &zErrMsg );
+	if ( rc!=SQLITE_OK ) {
+		fprintf( stderr, "D SQL error: %s\n", zErrMsg );
+	}
+	sqlite3_close( db );
+#else 	/* ! USE_BINARY_DATA_SQLITE */
 	fclose( output );
 	fclose( config );
+#endif
 }
 
 #ifdef USED_IN_DAT2BIN
Index: src/Makefile.am
===================================================================
--- src/Makefile.am	(revision 885)
+++ src/Makefile.am	(working copy)
@@ -28,3 +28,9 @@ libchewing_la_LDFLAGS = \
 	-rpath $(libdir) \
 	-no-undefined \
 	-export-symbols-regex "^(chewing)_"
+
+if ENABLE_BINARY_DATA_SQLITE
+INCLUDES += $(SQLITE3_CFLAGS)
+libchewing_la_LDFLAGS += $(SQLITE3_LIBS)
+endif
+
Index: src/choice.c
===================================================================
--- src/choice.c	(revision 885)
+++ src/choice.c	(working copy)
@@ -25,18 +25,11 @@
 #include "global.h"
 #include "dict-private.h"
 #include "char-private.h"
-#include "tree-private.h"
 #include "chewingutil.h"
 #include "userphrase-private.h"
 
 #define CEIL_DIV( a, b ) 	( ( a + b - 1 ) / b )
 
-#ifdef USE_BINARY_DATA
-TreeType *tree = NULL;
-#else
-TreeType tree[ TREE_SIZE ];
-#endif
-
 static void ChangeSelectIntervalAndBreakpoint(
 		ChewingData *pgdata,
 		int from,
Index: configure.ac
===================================================================
--- configure.ac	(revision 885)
+++ configure.ac	(working copy)
@@ -79,8 +79,13 @@ AC_FUNC_MALLOC
 AC_FUNC_MEMCMP
 AC_CHECK_FUNCS([memchr memmove memset mkdir strchr strstr])
 
+# optional modules
+CHECK_REQUIRED_VERSION=0.9.4
+SQLITE_REQUIRED_VERSION=3.0
+
 # Checks for check unit test framework
-PKG_CHECK_MODULES(CHECK, check >= 0.9.4, enable_check=yes, enble_check=no)
+PKG_CHECK_MODULES(CHECK, check >= $CHECK_REQUIRED_VERSION,
+		  enable_check=yes, enble_check=no)
 AM_CONDITIONAL(ENABLE_UNIT_TEST, test x$enable_check = "xyes")
 
 # Checks for ncursesw
@@ -169,15 +174,38 @@ AC_ARG_ENABLE([binary-data],
 		binary_data="no"
 		;;
 		*)
+		binary_data="yes"
 		;;
-		esac],
-	      [binary_data="yes"])
+		esac],)
 if test x$binary_data = "xyes"; then
 	AC_DEFINE(USE_BINARY_DATA, 1, [Experimental use of binary data])
 fi
-AC_SUBST(ENABLE_BINARY_DATA)
 AM_CONDITIONAL(ENABLE_BINARY_DATA, test x$binary_data = "xyes")
 
+AC_ARG_ENABLE([sqlite],
+		[AS_HELP_STRING([--enable-sqlite],
+				[Experimental use of SQLite3 for binary data @<:@default=no@:>@])],
+		[case "${enableval}" in
+		yes)
+		binary_data_sqlite="yes"
+		;;
+		*)
+		;;
+		esac],
+	      [binary_data_sqlite="no"])
+if test x$binary_data = "xyes" -a x$binary_data_sqlite = "xyes"; then
+	PKG_CHECK_MODULES([SQLITE3], [sqlite3 >= $SQLITE_REQUIRED_VERSION])
+	AC_SUBST([SQLITE3_CFLAGS])
+	AC_SUBST([SQLITE3_LIBS])
+	AC_DEFINE(USE_BINARY_DATA_SQLITE, 1,
+                  [Experimental use of SQLite 3 for binary data])
+else
+	binary_data_sqlite="no"
+fi
+AM_CONDITIONAL(ENABLE_BINARY_DATA_SQLITE,
+               test x$binary_data_sqlite = "xyes")
+
+
 # Platform-dependent
 dnl What kind of system are we using?
 case $host_os in
@@ -217,12 +245,18 @@ AC_OUTPUT([
 	Doxyfile
 ])
 
-AC_MSG_RESULT([
-Build options:
-  Version                 $PACKAGE_VERSION
-  Install prefix          $prefix
-  Enable debug            $LIBDEBUG
-  Enable binary data      $binary_data
-  Build Unit Test         $enable_check
-  Build TextUI sample     $enable_ncursesw
-])
+AC_OUTPUT
+
+echo 
+echo Build options:
+echo "  Version                 $PACKAGE_VERSION"
+echo "  Install prefix          $prefix"
+echo "  Enable debug            $LIBDEBUG"
+echo "  Enable binary data      $binary_data"
+if test x$binary_data = "xyes"; then
+echo "    +- SQLite support     $binary_data_sqlite"
+fi
+echo "  Build Unit Test         $enable_check"
+echo "  Build TextUI sample     $enable_ncursesw"
+echo 
+
Index: data/Makefile.am
===================================================================
--- data/Makefile.am	(revision 885)
+++ data/Makefile.am	(working copy)
@@ -26,9 +26,19 @@ gendata:
 if ENABLE_BINARY_DATA
 convert_dat:
 	$(tooldir)/dat2bin
-gendata2: ch_index.dat_bin fonetree.dat_bin ph_index.dat_bin
+GENERATED_DATA_LIST = ch_index.dat_bin ph_index.dat_bin
+if ENABLE_BINARY_DATA_SQLITE
+else
+GENERATED_DATA_LIST += fonetree.dat_bin
+endif
+gendata2: $(GENERATED_DATA_LIST)
 	-mv -f ch_index.dat_bin ch_index.dat
+if ENABLE_BINARY_DATA_SQLITE
+	-rm -f fonetree.dat
+	$(tooldir)/maketree
+else
 	-mv -f fonetree.dat_bin fonetree.dat
+endif
 	-mv -f ph_index.dat_bin ph_index.dat
 else
 	$(tooldir)/sort_word