ADDED   ext/session/changeset.c
Index: ext/session/changeset.c
==================================================================
--- /dev/null
+++ ext/session/changeset.c
@@ -0,0 +1,412 @@
+/*
+** 2014-08-18
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code to implement the "changeset" command line
+** utility for displaying and transforming changesets generated by
+** the Sessions extension.
+*/
+#include "sqlite3.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <ctype.h>
+
+
+/*
+** Show a usage message on stderr then quit.
+*/
+static void usage(const char *argv0){
+  fprintf(stderr, "Usage: %s FILENAME COMMAND ...\n", argv0);
+  fprintf(stderr,
+    "COMMANDs:\n"
+    "   apply DB           Apply the changeset to database file DB\n"
+    "   concat FILE2 OUT   Concatenate FILENAME and FILE2 into OUT\n"
+    "   dump               Show the complete content of the changeset\n"
+    "   invert OUT         Write an inverted changeset into file OUT\n"
+    "   sql                Give a pseudo-SQL rendering of the changeset\n"
+  );
+  exit(1);
+}
+
+/*
+** Read the content of a disk file into an in-memory buffer
+*/
+static void readFile(const char *zFilename, int *pSz, void **ppBuf){
+  FILE *f;
+  int sz;
+  void *pBuf;
+  f = fopen(zFilename, "rb");
+  if( f==0 ){
+    fprintf(stderr, "cannot open \"%s\" for reading\n", zFilename);
+    exit(1);
+  }
+  fseek(f, 0, SEEK_END);
+  sz = (int)ftell(f);
+  rewind(f);
+  pBuf = sqlite3_malloc( sz ? sz : 1 );
+  if( pBuf==0 ){
+    fprintf(stderr, "cannot allocate %d to hold content of \"%s\"\n",
+            sz, zFilename);
+    exit(1);
+  }
+  if( sz>0 ){
+    if( fread(pBuf, sz, 1, f)!=1 ){
+      fprintf(stderr, "cannot read all %d bytes of \"%s\"\n", sz, zFilename);
+      exit(1);
+    }
+    fclose(f);
+  }
+  *pSz = sz;
+  *ppBuf = pBuf;
+}
+
+/* Array for converting from half-bytes (nybbles) into ASCII hex
+** digits. */
+static const char hexdigits[] = {
+  '0', '1', '2', '3', '4', '5', '6', '7',
+  '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' 
+};
+
+/*
+** Render an sqlite3_value as an SQL string.
+*/
+static void renderValue(sqlite3_value *pVal){
+  switch( sqlite3_value_type(pVal) ){
+    case SQLITE_FLOAT: {
+      double r1;
+      char zBuf[50];
+      r1 = sqlite3_value_double(pVal);
+      sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.15g", r1);
+      printf("%s", zBuf);
+      break;
+    }
+    case SQLITE_INTEGER: {
+      printf("%lld", sqlite3_value_int64(pVal));
+      break;
+    }
+    case SQLITE_BLOB: {
+      char const *zBlob = sqlite3_value_blob(pVal);
+      int nBlob = sqlite3_value_bytes(pVal);
+      int i;
+      printf("x'");
+      for(i=0; i<nBlob; i++){
+        putchar(hexdigits[(zBlob[i]>>4)&0x0F]);
+        putchar(hexdigits[(zBlob[i])&0x0F]);
+      }
+      putchar('\'');
+      break;
+    }
+    case SQLITE_TEXT: {
+      const unsigned char *zArg = sqlite3_value_text(pVal);
+      putchar('\'');
+      while( zArg[0] ){
+        putchar(zArg[0]);
+        if( zArg[0]=='\'' ) putchar(zArg[0]);
+        zArg++;
+      }
+      putchar('\'');
+      break;
+    }
+    default: {
+      assert( sqlite3_value_type(pVal)==SQLITE_NULL );
+      printf("NULL");
+      break;
+    }
+  }
+}
+
+/*
+** Number of conflicts seen
+*/
+static int nConflict = 0;
+
+/*
+** The conflict callback
+*/
+static int conflictCallback(
+  void *pCtx,
+  int eConflict,
+  sqlite3_changeset_iter *pIter
+){
+  int op, bIndirect, nCol, i;
+  const char *zTab;
+  unsigned char *abPK;
+  const char *zType = "";
+  const char *zOp = "";
+  const char *zSep = " ";
+
+  nConflict++;
+  sqlite3changeset_op(pIter, &zTab, &nCol, &op, &bIndirect);
+  sqlite3changeset_pk(pIter, &abPK, 0);
+  switch( eConflict ){
+    case SQLITE_CHANGESET_DATA:         zType = "DATA";         break;
+    case SQLITE_CHANGESET_NOTFOUND:     zType = "NOTFOUND";     break;
+    case SQLITE_CHANGESET_CONFLICT:     zType = "PRIMARY KEY";  break;
+    case SQLITE_CHANGESET_FOREIGN_KEY:  zType = "FOREIGN KEY";  break;
+    case SQLITE_CHANGESET_CONSTRAINT:   zType = "CONSTRAINT";   break;
+  }
+  switch( op ){
+    case SQLITE_UPDATE:     zOp = "UPDATE of";     break;
+    case SQLITE_INSERT:     zOp = "INSERT into";   break;
+    case SQLITE_DELETE:     zOp = "DELETE from";   break;
+  }
+  printf("%s conflict on %s table %s with primary key", zType, zOp, zTab);
+  for(i=0; i<nCol; i++){
+    sqlite3_value *pVal;
+    if( abPK[i]==0 ) continue;
+    printf("%s", zSep);
+    if( op==SQLITE_INSERT ){
+      sqlite3changeset_new(pIter, i, &pVal);
+    }else{
+      sqlite3changeset_old(pIter, i, &pVal);
+    }
+    renderValue(pVal);
+    zSep = ",";
+  }
+  printf("\n");
+  return SQLITE_CHANGESET_OMIT;
+}
+
+int main(int argc, char **argv){
+  int sz, rc;
+  void *pBuf = 0;
+  if( argc<3 ) usage(argv[0]);
+  readFile(argv[1], &sz, &pBuf);
+
+  /* changeset FILENAME apply DB
+  ** Apply the changeset in FILENAME to the database file DB
+  */
+  if( strcmp(argv[2],"apply")==0 ){
+    sqlite3 *db;
+    if( argc!=4 ) usage(argv[0]);
+    rc = sqlite3_open(argv[3], &db);
+    if( rc!=SQLITE_OK ){
+      fprintf(stderr, "unable to open database file \"%s\": %s\n",
+              argv[3], sqlite3_errmsg(db));
+      sqlite3_close(db);
+      exit(1);
+    }
+    sqlite3_exec(db, "BEGIN", 0, 0, 0);
+    nConflict = 0;
+    rc = sqlite3changeset_apply(db, sz, pBuf, 0, conflictCallback, 0);
+    if( rc ){
+      fprintf(stderr, "sqlite3changeset_apply() returned %d\n", rc);
+    }
+    if( nConflict ){
+      fprintf(stderr, "%d conflicts - no changes applied\n", nConflict);
+      sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
+    }else if( rc ){
+      fprintf(stderr, "sqlite3changeset_apply() returns %d "
+                      "- no changes applied\n", rc);
+      sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
+    }else{
+      sqlite3_exec(db, "COMMIT", 0, 0, 0);
+    }
+    sqlite3_close(db);
+  }else
+
+  /* changeset FILENAME concat FILE2 OUT
+  ** Add changeset FILE2 onto the end of the changeset in FILENAME
+  ** and write the result into OUT.
+  */
+  if( strcmp(argv[2],"concat")==0 ){
+    int szB;
+    void *pB;
+    int szOut;
+    void *pOutBuf;
+    FILE *out;
+    const char *zOut = argv[4];
+    if( argc!=5 ) usage(argv[0]);
+    out = fopen(zOut, "wb");
+    if( out==0 ){
+      fprintf(stderr, "cannot open \"%s\" for writing\n", zOut);
+      exit(1);
+    }
+    readFile(argv[3], &szB, &pB);
+    sqlite3changeset_concat(sz, pBuf, szB, pB, &szOut, &pOutBuf);
+    if( fwrite(pOutBuf, szOut, 1, out)!=1 ){
+      fprintf(stderr, "unable to write all %d bytes of output to \"%s\"\n",
+              szOut, zOut);
+    }
+    fclose(out);
+    sqlite3_free(pOutBuf);
+    sqlite3_free(pB);
+  }else
+
+  /* changeset FILENAME dump
+  ** Show the complete content of the changeset in FILENAME
+  */
+  if( strcmp(argv[2],"dump")==0 ){
+    int cnt = 0;
+    int i;
+    sqlite3_changeset_iter *pIter;
+    rc = sqlite3changeset_start(&pIter, sz, pBuf);
+    if( rc!=SQLITE_OK ){
+      fprintf(stderr, "sqlite3changeset_start() returns %d\n", rc);
+      exit(1);
+    }
+    while( sqlite3changeset_next(pIter)==SQLITE_ROW ){
+      int op, bIndirect, nCol;
+      const char *zTab;
+      unsigned char *abPK;
+      sqlite3changeset_op(pIter, &zTab, &nCol, &op, &bIndirect);
+      cnt++;
+      printf("%d: %s table=[%s] indirect=%d nColumn=%d\n",
+             cnt, op==SQLITE_INSERT ? "INSERT" :
+                       op==SQLITE_UPDATE ? "UPDATE" : "DELETE",
+             zTab, bIndirect, nCol);
+      sqlite3changeset_pk(pIter, &abPK, 0);
+      for(i=0; i<nCol; i++){
+        sqlite3_value *pVal;
+        pVal = 0;
+        sqlite3changeset_old(pIter, i, &pVal);
+        if( pVal ){
+          printf("    old[%d]%s = ", i, abPK[i] ? "pk" : "  ");
+          renderValue(pVal);
+          printf("\n");
+        }
+        pVal = 0;
+        sqlite3changeset_new(pIter, i, &pVal);
+        if( pVal ){
+          printf("    new[%d]%s = ", i, abPK[i] ? "pk" : "  ");
+          renderValue(pVal);
+          printf("\n");
+        }
+      }
+    }
+    sqlite3changeset_finalize(pIter);
+  }else
+
+  /* changeset FILENAME invert OUT
+  ** Invert the changes in FILENAME and writes the result on OUT
+  */
+  if( strcmp(argv[2],"invert")==0 ){
+    FILE *out;
+    int szOut = 0;
+    void *pOutBuf = 0;
+    const char *zOut = argv[3];
+    if( argc!=4 ) usage(argv[0]);
+    out = fopen(zOut, "wb");
+    if( out==0 ){
+      fprintf(stderr, "cannot open \"%s\" for writing\n", zOut);
+      exit(1);
+    }
+    sqlite3changeset_invert(sz, pBuf, &szOut, &pOutBuf);
+    if( fwrite(pOutBuf, szOut, 1, out)!=1 ){
+      fprintf(stderr, "unable to write all %d bytes of output to \"%s\"\n",
+              szOut, zOut);
+    }
+    fclose(out);
+    sqlite3_free(pOutBuf);
+  }else
+
+  /* changeset FILE sql
+  ** Show the content of the changeset as pseudo-SQL
+  */
+  if( strcmp(argv[2],"sql")==0 ){
+    int cnt = 0;
+    char *zPrevTab = 0;
+    char *zSQLTabName = 0;
+    sqlite3_changeset_iter *pIter = 0;
+    rc = sqlite3changeset_start(&pIter, sz, pBuf);
+    if( rc!=SQLITE_OK ){
+      fprintf(stderr, "sqlite3changeset_start() returns %d\n", rc);
+      exit(1);
+    }
+    printf("BEGIN;\n");
+    while( sqlite3changeset_next(pIter)==SQLITE_ROW ){
+      int op, bIndirect, nCol;
+      const char *zTab;
+      sqlite3changeset_op(pIter, &zTab, &nCol, &op, &bIndirect);
+      cnt++;
+      if( zPrevTab==0 || strcmp(zPrevTab,zTab)!=0 ){
+        sqlite3_free(zPrevTab);
+        sqlite3_free(zSQLTabName);
+        zPrevTab = sqlite3_mprintf("%s", zTab);
+        if( !isalnum(zTab[0]) || sqlite3_strglob("*[^a-zA-Z0-9]*",zTab)==0 ){
+          zSQLTabName = sqlite3_mprintf("\"%w\"", zTab);
+        }else{
+          zSQLTabName = sqlite3_mprintf("%s", zTab);
+        }
+        printf("/****** Changes for table %s ***************/\n", zSQLTabName);
+      }
+      switch( op ){
+        case SQLITE_DELETE: {
+          unsigned char *abPK;
+          int i;
+          const char *zSep = " ";
+          sqlite3changeset_pk(pIter, &abPK, 0);
+          printf("/* %d */ DELETE FROM %s WHERE", cnt, zSQLTabName);
+          for(i=0; i<nCol; i++){
+            sqlite3_value *pVal;
+            if( abPK[i]==0 ) continue;
+            printf("%sc%d=", zSep, i+1);
+            zSep = " AND ";
+            sqlite3changeset_old(pIter, i, &pVal);
+            renderValue(pVal);
+          }
+          printf(";\n");
+          break;
+        }
+        case SQLITE_UPDATE: {
+          unsigned char *abPK;
+          int i;
+          const char *zSep = " ";
+          sqlite3changeset_pk(pIter, &abPK, 0);
+          printf("/* %d */ UPDATE %s SET", cnt, zSQLTabName);
+          for(i=0; i<nCol; i++){
+            sqlite3_value *pVal = 0;
+            sqlite3changeset_new(pIter, i, &pVal);
+            if( pVal ){
+              printf("%sc%d=", zSep, i+1);
+              zSep = ", ";
+              renderValue(pVal);
+            }
+          }
+          printf(" WHERE");
+          zSep = " ";
+          for(i=0; i<nCol; i++){
+            sqlite3_value *pVal;
+            if( abPK[i]==0 ) continue;
+            printf("%sc%d=", zSep, i+1);
+            zSep = " AND ";
+            sqlite3changeset_old(pIter, i, &pVal);
+            renderValue(pVal);
+          }
+          printf(";\n");
+          break;
+        }
+        case SQLITE_INSERT: {
+          int i;
+          printf("/* %d */ INSERT INTO %s VALUES", cnt, zSQLTabName);
+          for(i=0; i<nCol; i++){
+            sqlite3_value *pVal;
+            printf("%c", i==0 ? '(' : ',');
+            sqlite3changeset_new(pIter, i, &pVal);
+            renderValue(pVal);
+          }
+          printf(");\n");
+          break;
+        }
+      }
+    }
+    printf("COMMIT;\n");
+    sqlite3changeset_finalize(pIter);
+    sqlite3_free(zPrevTab);
+    sqlite3_free(zSQLTabName);
+  }else
+
+  /* If nothing else matches, show the usage comment */
+  usage(argv[0]);
+  sqlite3_free(pBuf);
+  return 0; 
+}

Index: main.mk
==================================================================
--- main.mk
+++ main.mk
@@ -70,10 +70,12 @@
          table.o tokenize.o trigger.o \
          update.o util.o vacuum.o \
          vdbeapi.o vdbeaux.o vdbeblob.o vdbemem.o vdbesort.o \
 	 vdbetrace.o wal.o walker.o where.o utf.o vtab.o
 
+LIBOBJ += sqlite3session.o
+
 
 
 # All of the source code files.
 #
 SRC = \
@@ -561,10 +563,13 @@
 	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_write.c
 
 rtree.o:	$(TOP)/ext/rtree/rtree.c $(HDR) $(EXTHDR)
 	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/rtree/rtree.c
 
+sqlite3session.o:	$(TOP)/ext/session/sqlite3session.c $(HDR) $(EXTHDR)
+	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/session/sqlite3session.c
+
 
 # Rules for building test programs and for running tests
 #
 tclsqlite3:	$(TOP)/src/tclsqlite.c libsqlite3.a
 	$(TCCX) $(TCL_FLAGS) -DTCLSH=1 -o tclsqlite3 \
@@ -652,10 +657,14 @@
 		$(TOP)/tool/showjournal.c sqlite3.o $(THREADLIB)
 
 showwal$(EXE):	$(TOP)/tool/showwal.c sqlite3.o
 	$(TCC) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION -o showwal$(EXE) \
 		$(TOP)/tool/showwal.c sqlite3.o $(THREADLIB)
+
+changeset$(EXE):	$(TOP)/ext/session/changeset.c sqlite3.o
+	$(TCC) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION -o changeset$(EXE) \
+		$(TOP)/ext/session/changeset.c sqlite3.o $(THREADLIB)
 
 fts3view$(EXE):	$(TOP)/ext/fts3/tool/fts3view.c sqlite3.o
 	$(TCC) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION -o fts3view$(EXE) \
 		$(TOP)/ext/fts3/tool/fts3view.c sqlite3.o $(THREADLIB)
 

Index: src/shell.c
==================================================================
--- src/shell.c
+++ src/shell.c
@@ -430,10 +430,23 @@
 #endif
   }
   return zResult;
 }
 
+#if defined(SQLITE_ENABLE_SESSION)
+/*
+** State information for a single open session
+*/
+typedef struct OpenSession OpenSession;
+struct OpenSession {
+  char *zName;             /* Symbolic name for this session */
+  int nFilter;             /* Number of xFilter rejection GLOB patterns */
+  char **azFilter;         /* Array of xFilter rejection GLOB patterns */
+  sqlite3_session *p;      /* The open session */
+};
+#endif
+
 /*
 ** Shell output mode information from before ".explain on", 
 ** saved so that it can be restored by ".explain off"
 */
 typedef struct SavedModeInfo SavedModeInfo;
@@ -477,10 +490,14 @@
   sqlite3_stmt *pStmt;   /* Current statement if any. */
   FILE *pLog;            /* Write log output here */
   int *aiIndent;         /* Array of indents used in MODE_Explain */
   int nIndent;           /* Size of array aiIndent[] */
   int iIndent;           /* Index of current op in aiIndent[] */
+#if defined(SQLITE_ENABLE_SESSION)
+  int nSession;             /* Number of active sessions */
+  OpenSession aSession[4];  /* Array of sessions.  [0] is in focus. */
+#endif
 };
 
 /*
 ** These are the allowed modes.
 */
@@ -1634,10 +1651,13 @@
   ".schema ?TABLE?        Show the CREATE statements\n"
   "                         If TABLE specified, only show tables matching\n"
   "                         LIKE pattern TABLE.\n"
   ".separator STRING ?NL? Change separator used by output mode and .import\n"
   "                         NL is the end-of-line mark for CSV\n"
+#if defined(SQLITE_ENABLE_SESSION)
+  ".session CMD ...       Create or control sessions\n"
+#endif
   ".shell CMD ARGS...     Run CMD ARGS... in a system shell\n"
   ".show                  Show the current values for various settings\n"
   ".stats on|off          Turn stats on or off\n"
   ".system CMD ARGS...    Run CMD ARGS... in a system shell\n"
   ".tables ?TABLE?        List names of tables\n"
@@ -1648,10 +1668,34 @@
   ".trace FILE|off        Output each SQL statement as it is run\n"
   ".vfsname ?AUX?         Print the name of the VFS stack\n"
   ".width NUM1 NUM2 ...   Set column widths for \"column\" mode\n"
   "                         Negative values right-justify\n"
 ;
+
+#if defined(SQLITE_ENABLE_SESSION)
+/*
+** Print help information for the ".sessions" command
+*/
+void session_help(ShellState *p){
+  fprintf(p->out,
+    ".session ?NAME? SUBCOMMAND ?ARGS...?\n"
+    "If ?NAME? is omitted, the first defined session is used.\n"
+    "Subcommands:\n"
+    "   attach TABLE             Attach TABLE\n"
+    "   changeset FILE           Write a changeset into FILE\n"
+    "   close                    Close one session\n"
+    "   enable ?BOOLEAN?         Set or query the enable bit\n"
+    "   filter GLOB...           Reject tables matching GLOBs\n" 
+    "   indirect ?BOOLEAN?       Mark or query the indirect status\n"
+    "   isempty                  Query whether the session is empty\n"
+    "   list                     List currently open session names\n"
+    "   open DB NAME             Open a new session on DB\n"
+    "   patchset FILE            Write a patchset into FILE\n"
+  );
+}
+#endif
+
 
 /* Forward reference */
 static int process_input(ShellState *p, FILE *in);
 /*
 ** Implementation of the "readfile(X)" SQL function.  The entire content
@@ -1711,10 +1755,55 @@
     rc = fwrite(z, 1, sqlite3_value_bytes(argv[1]), out);
   }
   fclose(out);
   sqlite3_result_int64(context, rc);
 }
+
+#if defined(SQLITE_ENABLE_SESSION)
+/*
+** Close a single OpenSession object and release all of its associated
+** resources.
+*/
+static void session_close(OpenSession *pSession){
+  int i;
+  sqlite3session_delete(pSession->p);
+  sqlite3_free(pSession->zName);
+  for(i=0; i<pSession->nFilter; i++){
+    sqlite3_free(pSession->azFilter[i]);
+  }
+  sqlite3_free(pSession->azFilter);
+  memset(pSession, 0, sizeof(OpenSession));
+}
+#endif
+
+/*
+** Close all OpenSession objects and release all assocaited resources.
+*/
+static void session_close_all(ShellState *p){
+#if defined(SQLITE_ENABLE_SESSION)
+  int i;
+  for(i=0; i<p->nSession; i++){
+    session_close(&p->aSession[i]);
+  }
+  p->nSession = 0;
+#endif
+}
+
+/*
+** Implementation of the xFilter function for an open session.  Omit
+** any tables named by ".session filter" but let all other table through.
+*/
+#if defined(SQLITE_ENABLE_SESSION)
+static int session_filter(void *pCtx, const char *zTab){
+  OpenSession *pSession = (OpenSession*)pCtx;
+  int i;
+  for(i=0; i<pSession->nFilter; i++){
+    if( sqlite3_strglob(pSession->azFilter[i], zTab)==0 ) return 0;
+  }
+  return 1;
+}
+#endif
 
 /*
 ** Make sure the database is open.  If it is not, then open it.  If
 ** the database fails to open, print an error message and exit.
 */
@@ -2863,10 +2952,11 @@
     if( nArg>=2 ){
       p->zDbFilename = zNewFilename = sqlite3_mprintf("%s", azArg[1]);
     }
     open_db(p, 1);
     if( p->db!=0 ){
+      session_close_all(p);
       sqlite3_close(savedDb);
       sqlite3_free(p->zFreeOnClose);
       p->zFreeOnClose = zNewFilename;
     }else{
       sqlite3_free(zNewFilename);
@@ -3083,10 +3173,199 @@
       rc = 1;
     }else{
       rc = 0;
     }
   }else
+
+#if defined(SQLITE_ENABLE_SESSION)
+  if( c=='s' && strncmp(azArg[0],"session",n)==0 && n>=3 ){
+    OpenSession *pSession = &p->aSession[0];
+    char **azCmd = &azArg[1];
+    int iSes = 0;
+    int nCmd = nArg - 1;
+    int i;
+    if( nArg<=1 ) goto session_syntax_error;
+    open_db(p, 0);
+    if( nArg>=3 ){
+      for(iSes=0; iSes<p->nSession; iSes++){
+        if( strcmp(p->aSession[iSes].zName, azArg[1])==0 ) break;
+      }
+      if( iSes<p->nSession ){
+        pSession = &p->aSession[iSes];
+        azCmd++;
+        nCmd--;
+      }else{
+        pSession = &p->aSession[0];
+        iSes = 0;
+      }
+    }
+
+    /* .session attach TABLE
+    ** Invoke the sqlite3session_attach() interface to attach a particular
+    ** table so that it is never filtered.
+    */
+    if( strcmp(azCmd[0],"attach")==0 ){
+      if( nCmd!=2 ) goto session_syntax_error;
+      if( pSession->p==0 ){
+        session_not_open:
+        fprintf(stderr, "ERROR: No sessions are open\n");
+      }else{
+        rc = sqlite3session_attach(pSession->p, azCmd[1]);
+        if( rc ){
+          fprintf(stderr, "ERROR: sqlite3session_attach() returns %d\n", rc);
+          rc = 0;
+        }
+      }
+    }else
+
+    /* .session changeset FILE
+    ** .session patchset FILE
+    ** Write a changeset or patchset into a file.  The file is overwritten.
+    */
+    if( strcmp(azCmd[0],"changeset")==0 || strcmp(azCmd[0],"patchset")==0 ){
+      FILE *out = 0;
+      if( nCmd!=2 ) goto session_syntax_error;
+      if( pSession->p==0 ) goto session_not_open;
+      out = fopen(azCmd[1], "wb");
+      if( out==0 ){
+        fprintf(stderr, "ERROR: cannot open \"%s\" for writing\n", azCmd[1]);
+      }else{
+        int szChng;
+        void *pChng;
+        if( azCmd[0][0]=='c' ){
+          sqlite3session_changeset(pSession->p, &szChng, &pChng);
+        }else{
+          sqlite3session_patchset(pSession->p, &szChng, &pChng);
+        }
+        if( pChng 
+          && fwrite(pChng, szChng, 1, out)!=1 ){
+          fprintf(stderr, "ERROR: Failed to write entire %d-byte output\n",
+                  szChng);
+        }
+        sqlite3_free(pChng);
+        fclose(out);
+      }
+    }else
+
+    /* .session close
+    ** Close the identified session
+    */
+    if( strcmp(azCmd[0], "close")==0 ){
+      if( nCmd!=1 ) goto session_syntax_error;
+      if( p->nSession ){
+        session_close(pSession);
+        p->aSession[iSes] = p->aSession[--p->nSession];
+      }
+    }else
+
+    /* .session enable ?BOOLEAN?
+    ** Query or set the enable flag
+    */
+    if( strcmp(azCmd[0], "enable")==0 ){
+      int ii;
+      if( nCmd>2 ) goto session_syntax_error;
+      ii = nCmd==1 ? -1 : booleanValue(azCmd[1]);
+      if( p->nSession ){
+        ii = sqlite3session_enable(pSession->p, ii);
+        fprintf(p->out, "session %s enable flag = %d\n", pSession->zName, ii);
+      }
+    }else
+
+    /* .session filter GLOB ....
+    ** Set a list of GLOB patterns of table names to be excluded.
+    */
+    if( strcmp(azCmd[0], "filter")==0 ){
+      int ii, nByte;
+      if( nCmd<2 ) goto session_syntax_error;
+      if( p->nSession ){
+        for(ii=0; ii<pSession->nFilter; ii++){
+          sqlite3_free(pSession->azFilter[ii]);
+        }
+        sqlite3_free(pSession->azFilter);
+        nByte = sizeof(pSession->azFilter[0])*(nCmd-1);
+        pSession->azFilter = sqlite3_malloc( nByte );
+        if( pSession->azFilter==0 ){
+          fprintf(stderr, "Error: out or memory\n");
+          exit(1);
+        }
+        for(ii=1; ii<nCmd; ii++){
+          pSession->azFilter[ii-1] = sqlite3_mprintf("%s", azCmd[ii]); 
+        }
+        pSession->nFilter = ii-1;
+      }
+    }else
+
+    /* .session indirect ?BOOLEAN?
+    ** Query or set the indirect flag
+    */
+    if( strcmp(azCmd[0], "indirect")==0 ){
+      int ii;
+      if( nCmd>2 ) goto session_syntax_error;
+      ii = nCmd==1 ? -1 : booleanValue(azCmd[1]);
+      if( p->nSession ){
+        ii = sqlite3session_indirect(pSession->p, ii);
+        fprintf(p->out, "session %s indirect flag = %d\n", pSession->zName,ii);
+      }
+    }else
+
+    /* .session isempty
+    ** Determine if the session is empty
+    */
+    if( strcmp(azCmd[0], "isempty")==0 ){
+      int ii;
+      if( nCmd!=1 ) goto session_syntax_error;
+      if( p->nSession ){
+        ii = sqlite3session_isempty(pSession->p);
+        fprintf(p->out, "session %s isempty flag = %d\n", pSession->zName, ii);
+      }
+    }else
+
+    /* .session list
+    ** List all currently open sessions
+    */
+    if( strcmp(azCmd[0],"list")==0 ){
+      for(i=0; i<p->nSession; i++){
+        fprintf(p->out, "%d %s\n", i, p->aSession[i].zName);
+      }
+    }else
+
+    /* .session open DB NAME
+    ** Open a new session called NAME on the attached database DB.
+    ** DB is normally "main".
+    */
+    if( strcmp(azCmd[0],"open")==0 ){
+      char *zName;
+      if( nCmd!=3 ) goto session_syntax_error;
+      zName = azCmd[2];
+      if( zName[0]==0 ) goto session_syntax_error;
+      for(i=0; i<p->nSession; i++){
+        if( strcmp(p->aSession[i].zName,zName)==0 ){
+          fprintf(stderr, "Session \"%s\" already exists\n", zName);
+          goto meta_command_exit;
+        }
+      }
+      if( p->nSession>=ArraySize(p->aSession) ){
+        fprintf(stderr, "Maximum of %d sessions\n", ArraySize(p->aSession));
+        goto meta_command_exit;
+      }
+      pSession = &p->aSession[p->nSession];
+      rc = sqlite3session_create(p->db, azCmd[1], &pSession->p);
+      if( rc ){
+        fprintf(stderr, "Cannot open session: error code=%d\n", rc);
+        rc = 0;
+        goto meta_command_exit;
+      }
+      pSession->nFilter = 0;
+      sqlite3session_table_filter(pSession->p, session_filter, pSession);
+      p->nSession++;
+      pSession->zName = sqlite3_mprintf("%s", zName);
+    }else
+    /* If no command name matches, show a syntax error */
+    session_syntax_error:
+    session_help(p);
+  }else
+#endif
 
 #ifdef SQLITE_DEBUG
   /* Undocumented commands for internal testing.  Subject to change
   ** without notice. */
   if( c=='s' && n>=10 && strncmp(azArg[0], "selftest-", 9)==0 ){
@@ -4132,10 +4411,11 @@
       rc = process_input(&data, stdin);
     }
   }
   set_table_name(&data, 0);
   if( data.db ){
+    session_close_all(&data);
     sqlite3_close(data.db);
   }
   sqlite3_free(data.zFreeOnClose); 
   return rc;
 }