--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/s4-world.sh	Sat Jun 06 11:43:42 2020 +0900
@@ -0,0 +1,72 @@
+#!/bin/sh
+
+if [ -z "$S4MASTERDB" -o ! -s "$S4MASTERDB" ]; then
+  return
+fi
+if [ "$db" -ef "$S4MASTERDB" ]; then
+  return		# Points to the same file
+fi
+
+# Now Another world is ACTIVE
+# sessdb=`dirname $S4MASTERDB`/sess.sq3
+## skey="skey-`basename $mydir`"
+S4NAME="[$S4WORLD]$S4NAME"
+syncflag=${db%.*}.synctime
+userupdateflag=`dirname $S4MASTERDB`/`basename $userupdateflag`
+test ! -e "$userupdateflag"		&& return
+test "$syncflag" -nt "$userupdateflag"	&& return
+
+#  for sub.sq3
+# 
+#  main: user: 'taro', 'hanako', 'shige'
+#  sub:  user: 'taro', 'hanako', 'shige'
+#  sub2: user_s: ('taro', 't'), ('hanako', 'h'), ('shige', 's')
+#  then update
+# 
+
+## sqlite3 -cmd '.timer 1' -cmd '.echo 1' $db <<EOF
+err "Starting account synchronization"
+err "db=$db mas=$S4MASTERDB sessdb=$sessdb"
+num=$(sqlite3 -bail -cmd 'PRAGMA FOREIGN_KEYS=on' $db <<EOF
+ATTACH DATABASE "$S4MASTERDB" AS m;
+CREATE TABLE IF NOT EXISTS user(name, primary key(name));
+BEGIN;
+DElETE FROM main.user WHERE rowid NOT IN (SELECT rowid FROM m.user);
+INSERT INTO main.user(rowid, name)
+       SELECT rowid, name FROM m.user
+       WHERE m.user.rowid NOT IN (SELECT rowid FROM user);
+UPDATE user SET name = (SELECT name FROM m.user WHERE main.user.rowid=m.user.rowid);
+DELETE FROM main.user_s WHERE rowid NOT IN (SELECT rowid FROM m.user_s);
+REPLACE INTO main.user_s(rowid, name, key, type, val, bin)
+	SELECT rowid,* FROM m.user_s;
+DELETE FROM main.user_m WHERE rowid NOT IN (SELECT rowid FROM m.user_m);
+REPLACE INTO main.user_m(rowid, name, key, type, val, bin)
+	SELECT rowid,* FROM m.user_m
+	WHERE key NOT LIKE '%cache%';
+END;
+
+/* Compare user tables */
+WITH master AS (
+  SELECT p.rowid,* FROM m.user p
+  	 NATURAL LEFT JOIN m.user_s
+	 NATURAL LEFT JOIN m.user_m
+), thisworld AS (
+  SELECT p.rowid,* FROM user p
+  	 NATURAL LEFT JOIN user_s
+ 	 NATURAL LEFT JOIN user_m
+), m_a AS (
+  SELECT * FROM master EXCEPT SELECT * FROM thisworld
+), a_m AS (
+  SELECT * FROM thisworld EXCEPT SELECT * FROM master
+) SELECT (SELECT count(*) FROM m_a) + (SELECT count(*) FROM a_m);
+
+-- SELECT * FROM thisworld;
+-- SELECT rowid,* FROM m.user LIMIT 10;
+-- SELECT rowid,* FROM user WHERE rowid NOT IN (SELECT rowid FROM m.user);
+DETACH DATABASE m;
+EOF
+)
+if [ $num -eq 0 ]; then
+  touch $syncflag
+fi
+return $num