android - My Database is not working -

i have tried implement database in android , while running application getting stopped without entering in activities. giving log cat below,i need suggestions overcome error.

   08-16 05:40:15.381: e/androidruntime(1096): fatal exception: main    08-16 05:40:15.381: e/androidruntime(1096): java.lang.runtimeexception: unable start activity componentinfo{com.de.vogella.android.sqlite.first/com.de.vogella.android.sqlite.first.testdatabaseactivity}: android.database.sqlite.sqliteexception: near "tablecomments": syntax error (code 1): , while compiling: create tablecomments(_idinteger primary key autoincrementcommenttext not null);    08-16 05:40:15.381: e/androidruntime(1096):  @ android.app.activitythread.performlaunchactivity(activitythread.java:2180)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.app.activitythread.handlelaunchactivity(activitythread.java:2230)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.app.activitythread.access$600(activitythread.java:141)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.app.activitythread$h.handlemessage(activitythread.java:1234)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.os.handler.dispatchmessage(handler.java:99)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.os.looper.loop(looper.java:137)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.app.activitythread.main(activitythread.java:5041)    08-16 05:40:15.381: e/androidruntime(1096):  @ java.lang.reflect.method.invokenative(native method)    08-16 05:40:15.381: e/androidruntime(1096):  @ java.lang.reflect.method.invoke(method.java:511)    08-16 05:40:15.381: e/androidruntime(1096):  @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:793)    08-16 05:40:15.381: e/androidruntime(1096):  @ com.android.internal.os.zygoteinit.main(zygoteinit.java:560)    08-16 05:40:15.381: e/androidruntime(1096):  @ dalvik.system.nativestart.main(native method)    08-16 05:40:15.381: e/androidruntime(1096): caused by: android.database.sqlite.sqliteexception: near "tablecomments": syntax error (code 1): , while compiling: create tablecomments(_idinteger primary key autoincrementcommenttext not null);    08-16 05:40:15.381: e/androidruntime(1096):  @ android.database.sqlite.sqliteconnection.nativepreparestatement(native method)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.database.sqlite.sqliteconnection.acquirepreparedstatement(sqliteconnection.java:882)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.database.sqlite.sqliteconnection.prepare(sqliteconnection.java:493)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.database.sqlite.sqlitesession.prepare(sqlitesession.java:588)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.database.sqlite.sqliteprogram.<init>(sqliteprogram.java:58)    08-16 05:40:15.381: e/androidruntime(1096):  @ android.database.sqlite.sqlitestatement.<init>(sqlitestatement.java:31) 

it says syntax error think couldn't find ..giving code below

     public class mysqlitehelper extends sqliteopenhelper {    public static final string table_comments="comments"; public static final string column_id="_id"; public static final string column_comment="comment"; private static final string database_name="comments.db"; private static int database_version=1;  //database creation  sql statements       private static final string database_create="create table"+table_comments+"       ("+column_id+"integer primary key autoincrement"+column_comment+"text not null);";       public mysqlitehelper(context context) {  super(context, database_name, null, database_version);  // todo auto-generated constructor stub      }        @override      public void oncreate(sqlitedatabase database) {   // todo auto-generated method stub        database.execsql(database_create);        }        @override        public void onupgrade(sqlitedatabase db, int oldversion, int newversion) {    // todo auto-generated method stub   log.w(mysqlitehelper.class.getname(),"upgrading database  version "+         oldversion+"to"+newversion+",which destroy data");        db.execsql("drop table if exists"+table_comments);       oncreate(db);         }      } 

you're missing few spaces in create statement.

try using:

private static final string database_create="create table " + table_comments + " (" + column_id + " integer primary key autoincrement " + column_comment + " text not null);"