[Feature] Issue#43 Add Column Dynamically

Description:
------------
The original adding column will move the data. it will consume long time.
Now the new row_format COMFORT for InnoDB can add column dynamically.

The innodb comfort record format such as:
  [lens | n_nulls | n_fields | extra | id...]
    1. extra info_bits will occupy 1 bit to flag comfort.
    2. n_fields will occupy 1 or 2 bytes to save the column number.

Then add column action will only change the dictionary and cache.

Limition:
---------
The column only can added at last, and nullable, non-default value.

Usage:
------
create table t (id int) engine=innodb row_format=comfort.
alter table t add col1 int;

include/mysql_com.h

@@ -126,6 +126,7 @@ enum enum_server_command
 #define FIELD_FLAGS_COLUMN_FORMAT_MASK (3 << FIELD_FLAGS_COLUMN_FORMAT)
 #define FIELD_IS_DROPPED (1<< 26)       /* Intern: Field is being dropped */
 #define CLUSTERING_FLAG  (1<< 27)       /* Field has a secondary clustering key */
+#define FIELD_IS_ADDED   (1<< 28)       /* Intern: Field is being added */
 
 #define REFRESH_GRANT		1	/* Refresh grant tables */
 #define REFRESH_LOG		2	/* Start on new log file */

mysql-test/t/feature_inplace_column-master.opt

@@ -0,0 +1 @@
+--binlog_format=row

mysql-test/t/feature_inplace_column-slave.opt

@@ -0,0 +1 @@
+--binlog_format=row

mysql-test/t/feature_inplace_column_2-master.opt

@@ -0,0 +1 @@
+--binlog_format=row

mysql-test/t/feature_inplace_column_2-slave.opt

@@ -0,0 +1 @@
+--binlog_format=row

mysql-test/t/feature_inplace_column_2.test

@@ -0,0 +1,264 @@
+--source include/master-slave.inc
+--source include/have_innodb.inc
+--source include/have_binlog_format_row.inc
+
+connection master;
+use test;
+create table t( col varchar(200) default 'xpchild',
+		col1 int,
+		col2 char(100),
+		col3 varchar(100),
+                key ind(col),
+		key ind_1(col1),
+		key ind_2(col2),
+		key ind_3(col3))engine=innodb row_format=comfort;
+
+
+insert into t(col, col1, col2, col3)  values('xp1', 2, 'xp', 'xpchild');
+insert into t(col, col1, col2, col3)  values('xp2', 2, 'xp', 'xpchild');
+commit;
+
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+insert into t(col1, col2, col3) select col1, col2, col3 from t;
+
+###########################################################################
+
+select count(*) from t;
+checksum table t;
+
+alter table t add col4 varchar(1000);
+select col4 from t limit 10;
+checksum table t;
+
+update t set col4=concat(col3, col1);
+commit;
+select col4 from t limit 10;
+checksum table t;
+
+###########################################################################
+
+--echo ###########################################
+--echo delete and insert same record
+--echo ###########################################
+delete from t where col='xp1';
+insert into t values('xp1', 2, 'xp', 'xpchild', 'xp');
+commit;
+select * from t where col='xp1';
+
+--echo ###########################################
+--echo create index on added column
+--echo ###########################################
+create index t_ind_4 on t(col4);
+select * from t where col4='xp';
+
+--echo ###########################################
+--echo alter table add more than one column
+--echo ###########################################
+alter table t add col5 int, add col6 int;
+select * from t where col='xp1';
+
+--echo ###########################################
+--echo alter table add clob column
+--echo ###########################################
+
+alter table t add col7 text;
+select * from t where col='xp1';
+
+update t set col7=repeat('xpchild', 10000) where col='xp1';
+commit;
+select * from t where col='xp1' or col ='xp2';
+
+--echo ###########################################
+--echo transport tablespace
+--echo ###########################################
+--let $MYSQLD_DATADIR= `SELECT @@datadir`
+connect (master_1,127.0.0.1,root,,test,$MASTER_MYPORT);
+connect (master_2,127.0.0.1,root,,test,$MASTER_MYPORT);
+
+connection master;
+show create table test.t;
+create database db_1;
+
+
+connection master_1;
+use test;
+flush table t for export;
+
+connection master_2;
+use db_1;
+create table t( col varchar(200) default 'xpchild',
+col1 int,
+col2 char(100),
+col3 varchar(100),
+col4 varchar(1000) DEFAULT NULL,
+col5 int(11) DEFAULT NULL,
+col6 int(11) DEFAULT NULL,
+col7 text,
+key ind(col),
+key ind_1(col1),
+key ind_2(col2),
+key ind_3(col3),
+KEY `t_ind_4` (`col4`(767))
+)engine=innodb row_format=comfort;
+
+set sql_log_bin=off;
+alter table t discard tablespace;
+
+--exec cp -rf $MYSQLD_DATADIR/test/t.cfg  $MYSQLD_DATADIR/db_1/
+--exec cp -rf $MYSQLD_DATADIR/test/t.ibd  $MYSQLD_DATADIR/db_1/
+
+alter table t import tablespace;
+select count(*) from t;
+show create table t;
+checksum table t;
+
+connection master_1;
+use test;
+unlock tables;
+
+
+connection master;
+checksum table db_1.t;
+checksum table test.t;
+drop table db_1.t;
+drop database db_1;
+
+
+--echo ###########################################
+--echo online copy data operation
+--echo ###########################################
+
+alter table t drop index ind_1;
+alter table t drop index ind_2;
+alter table t drop index ind_3;
+alter table t drop index t_ind_4;
+
+alter table t drop column col3, drop column col4, drop column col5, drop column col6, drop column col7;
+alter table t add col3 int default 10;
+alter table t row_format=compact;
+alter table t row_format=comfort;
+alter table t add col4 int;
+show create table t;
+select count(*) from t;
+checksum table t;
+
+
+--echo ###########################################
+--echo online dml operation
+--echo ###########################################
+
+connection master_1;
+use test;
+SET GLOBAL DEBUG='d,alter_table_sleep_for_online';
+
+--send alter table t add col5 int;
+
+connection master_2;
+use test;
+insert into t(col1, col2, col3, col4) select col1, col2, col3, col4 from t;
+update t set col2=concat(col2, col) where col= 'xp1';
+update t set col3=concat(col3, col) where col= 'xp2';
+update t set col='xp3' where col= 'xp1';
+select * from t where col='xp3';
+delete from t where col='xp2';
+commit;
+
+connection master_1;
+--reap
+
+
+connection master_1;
+use test;
+SET GLOBAL DEBUG='';
+show create table t;
+select count(*)  from t;
+checksum table t;
+
+insert into t(col, col1, col2, col3)  values('xp1', 2, 'xp', 'xpchild');
+insert into t(col, col1, col2, col3)  values('xp2', 2, 'xp', 'xpchild');
+commit;
+
+
+--echo ###########################################
+--echo online copy data  and dml operation
+--echo ###########################################
+
+connection master_1;
+use test;
+SET GLOBAL DEBUG='d,alter_table_sleep_for_online';
+
+--send alter table t add col6 int default 100;
+
+connection master_2;
+use test;
+insert into t(col1, col2, col3, col4) select col1, col2, col3, col4 from t;
+update t set col2=concat(col2, col) where col ='xp1';
+update t set col3=concat(col3, col) where col = 'xp2';
+update t set col='xp3' where col='xp1';
+select * from t where col='xp2';
+delete from t where col='xp2';
+commit;
+
+connection master_1;
+--reap
+
+connection master_1;
+use test;
+SET GLOBAL DEBUG='';
+show create table t;
+select count(*)  from t;
+checksum table t;
+
+
+insert into t(col, col1, col2, col3)  values('xp1', 2, 'xp', 'xpchild');
+insert into t(col, col1, col2, col3)  values('xp2', 2, 'xp', 'xpchild');
+commit;
+
+
+--echo ###########################################
+--echo online index data and dml operation
+--echo ###########################################
+
+connection master_1;
+use test;
+SET GLOBAL DEBUG='d,alter_table_sleep_for_online';
+
+--send alter table t add index ind_col4(col4);
+
+connection master_2;
+use test;
+insert into t(col1, col2, col3, col4) select col1, col2, col3, col4 from t;
+update t set col2=concat(col2, col) where col= 'xp1';
+update t set col3=concat(col3, col) where col= 'xp2';
+update t set col4=100 where col='xp2';
+delete from t where col='xp2';
+commit;
+
+connection master_1;
+--reap
+
+connection master_1;
+use test;
+SET GLOBAL DEBUG='';
+show create table t;
+select count(*)  from t;
+checksum table t;
+
+
+
+
+
+
+
+connection master;
+use test;
+drop table t;
+
+--sync_slave_with_master
+--source include/rpl_end.inc

sql/handler.cc

@@ -98,7 +98,7 @@ const char *ha_row_type[] = {
   "", "FIXED", "DYNAMIC", "COMPRESSED", "REDUNDANT", "COMPACT",
   /* Reserved to be "PAGE" in future versions */ "?",
   "TOKUDB_UNCOMPRESSED", "TOKUDB_ZLIB", "TOKUDB_QUICKLZ", "TOKUDB_LZMA",
-  "TOKUDB_FAST", "TOKUDB_SMALL",
+  "TOKUDB_FAST", "TOKUDB_SMALL", "COMFORT",
   "?","?","?"
 };
 

sql/handler.h

@@ -406,7 +406,7 @@ enum row_type { ROW_TYPE_NOT_USED=-1, ROW_TYPE_DEFAULT, ROW_TYPE_FIXED,
                 ROW_TYPE_PAGE,
                 ROW_TYPE_TOKU_UNCOMPRESSED, ROW_TYPE_TOKU_ZLIB,
                 ROW_TYPE_TOKU_QUICKLZ, ROW_TYPE_TOKU_LZMA,
-                ROW_TYPE_TOKU_FAST, ROW_TYPE_TOKU_SMALL };
+                ROW_TYPE_TOKU_FAST, ROW_TYPE_TOKU_SMALL, ROW_TYPE_COMFORT };
 
 
 /* Specifies data storage format for individual columns */
@@ -1235,6 +1235,11 @@ class Alter_inplace_info
   */
   static const HA_ALTER_FLAGS RECREATE_TABLE             = 1L << 29;
 
+  /**
+     Add column comfortably for ALTER TABLE ADD COLUMN.
+  */
+  static const HA_ALTER_FLAGS ADD_COLUMN_FOR_COMFORT     = 1L << 30;
+
   /**
     Create options (like MAX_ROWS) for the new version of table.
 

sql/lex.h

@@ -121,6 +121,7 @@ static SYMBOL symbols[] = {
   { "COLUMN_FORMAT",	SYM(COLUMN_FORMAT_SYM)},
   { "COLUMN_NAME",      SYM(COLUMN_NAME_SYM)},
   { "COLUMNS",		SYM(COLUMNS)},
+  { "COMFORT",		SYM(COMFORT_SYM)},
   { "COMMENT",		SYM(COMMENT_SYM)},
   { "COMMIT",		SYM(COMMIT_SYM)},
   { "COMMITTED",	SYM(COMMITTED_SYM)},

sql/sql_show.cc

@@ -4852,6 +4852,9 @@ static int get_schema_tables_record(THD *thd, TABLE_LIST *tables,
       case ROW_TYPE_COMPACT:
         tmp_buff= "Compact";
         break;
+      case ROW_TYPE_COMFORT:
+        tmp_buff= "Comfort";
+        break;
       case ROW_TYPE_PAGE:
         tmp_buff= "Paged";
         break;