Here is a list on constructed languages in ISO 639-3. See Creating statistics on ISO 639 language codes for how this was generated.

Versions of relevant table(s):

Constructed language list

Count of constructed language codes in ISO 639-3: 20
Query: SELECT COUNT(*) as count FROM ISO_639_3 WHERE Type='C'

I created a page showing simple ISO 639 language code statistics.

Creating this took some time as I had do figure out how to integrate that into PHP and I never did anything in that language before. Additionally though I already described how to load ISO 639-3 tables provided by SIL into MySQL, I had to make some changes to the given data, which I didn't do in the first place.

To not make MySQL search case sensitively it has to be told to use a proper collation. Where it seems needed I added it to the column specifications.

Steps:

• Downloading all the tables from SIL and LoC
• Modifying the database schemes, as I need indexing and keys:
  

  CREATE TABLE ISO_639_3 (
     Id      char(3) NOT NULL,  -- The three-letter 639-3 identifier
     Part2B  char(3) NULL,      -- Equivalent 639-2 identifier of the
                                -- bibliographic applications code set, if
                                -- there is one
     Part2T  char(3) NULL,      -- Equivalent 639-2 identifier of the terminology
                                -- applications code set, if there is one
     Part1   char(2) NULL,      -- Equivalent 639-1 identifier, if there is one
     Scope   char(1) NOT NULL,  -- I(ndividual), M(acrolanguage), S(pecial)
     Type    char(1) NOT NULL,  -- A(ncient), C(onstructed),
                                -- E(xtinct), H(istorical), L(iving), S(pecial)
     Ref_Name   varchar(150) collate utf8_general_ci NOT NULL,
                                -- Reference language name
     Comment    varchar(150) collate utf8_general_ci NULL,
                                -- Comment relating to one or more of the columns
     PRIMARY KEY (Id),
     INDEX (Part2B),
     INDEX (Part2T),
     INDEX (Part1)
  );
  
  CREATE TABLE ISO_639_3_Names (
     Id             char(3)     NOT NULL,  -- The three-letter 639-3 identifier
     Print_Name     varchar(75) collate utf8_general_ci NOT NULL,
                                           -- One of the names associated with
                                           -- this identifier
     Inverted_Name  varchar(75) collate utf8_general_ci NOT NULL,
                                           -- The inverted form of this
                                           -- Print_Name form
     INDEX (Id)
  );
  
  CREATE TABLE ISO_639_3_Macrolanguages (
     M_Id  char(3) NOT NULL,  -- The identifier for a macrolanguage
     I_Id  char(3) NOT NULL,  -- The identifier for an individual language
                              -- that is a member of the macrolanguage
     PRIMARY KEY (I_Id),
     INDEX (M_Id)
  );
  
  CREATE TABLE ISO_639_3_Retirements (
     Id          char(3)      NOT NULL,   -- The three-letter 639-3 identifier
     Ret_Reason  char(1)      NOT NULL,   -- code for retirement: C (change),
                                          -- D (duplicate), N (non-existent),
                                          -- S (split), M (merge)
     Change_To   char(3)      NULL,       -- in the cases of C, D, and M, the
                                          -- identifier to which all instances
                                          -- of this Id should be changed
     Ret_Remedy  varchar(200) NOT NULL,   -- The instructions for updating an
                                          -- instance of the retired (split)
                                          -- identifier
     Effective   date         NOT NULL,   -- The date the retirement became
                                          -- effective
     PRIMARY KEY (Id)
  );
  
  CREATE TABLE `ISO_639_2` (
     `Part2B` char(3) NOT NULL,
     `Part2T` char(3) default NULL,
     `Part1` char(2) default NULL,
     `Ref_Name_EN` varchar(150) collate utf8_general_ci NOT NULL,
     `Ref_Name_FR` varchar(150) collate utf8_general_ci NOT NULL,
     PRIMARY KEY (Part2B),
     INDEX (Part2T),
     INDEX (Part1)
  );
  

• I added another table for saving the timestamps of the respective tables and added the values:
  

  CREATE TABLE `Versions` (
   `Entity` char(50) NOT NULL,
   `Version` char(20) NOT NULL,
   PRIMARY KEY (Entity)
   );
  

  
insert into Versions values ('ISO 639-2', '20071029');
...


• Before importing the data files, I had to do a bit of a make up, as the Byte Order Mark (BOM) had to be removed and line break had to be added here and there as to allow the import with MySQL 5 methods.
• Then I used the LOAD DATA LOCAL FILE directive to import the text files into my local system (encoding utf8, downloaded files where created on a windows system, so use \r\n as line end):
  
LOAD DATA LOCAL INFILE 'iso-639-3-macrolanguages_20070801.tab' INTO TABLE ISO_639_3_Macrolanguages CHARACTER SET utf8 FIELDS TERMINATED BY '\t' LINES TERMINATED BY '\r\n' IGNORE 1 LINES;
...

• After that I had to transfer them to the server online, where I wouldn't have access to the local filesystem:
  
mysqldump --compatible=mysql40 --skip-lock-tables -p ISO639-3 > iso639codes.sql
cat iso639codes.sql | grep -v "LOCK TABLES" | grep -v "UNLOCK TABLES" > iso639codes_clean.sql

  I don't have lock table rights so I had to tell mysqldump to omit these commands. Furthermore I use 5.0 locally and 4.0 on the server (--compatible=mysql40).

  Uploading is then easy:
  
cat iso639codes_clean.sql | mysql -p -h "hostname" ISO639-3


• After that I had to create a page where I could quickly add SQL SELECTs as to generate quick statistics.
  Drupal makes it difficult here, as they have a way to access additional databases through drupal library methods, though not allowing to use PHP's own ones (which would screw up drupal), and interfering with the CMS system:
  
  user warning: Table 'ISO639-3.system' doesn't exist query: SELECT * FROM system WHERE type = 'theme' in /home/.../includes/database.mysql.inc on line 173.
  
• Finally I have data in the current versions:
  

  +--------------------------+----------+
  | Entity                   | Version  |
  +--------------------------+----------+
  | ISO 639-2                | 20071029 |
  | ISO 639-3                | 20071018 |
  | ISO 639-3 Name Index     | 20070814 |
  | ISO 639-3 Macrolanguages | 20070801 |
  | ISO 639-3 Retirements    | 20070814 |
  +--------------------------+----------+
  

• Some more interesting queries are hopefully yet to come, as I really think it's interesting to see those codes that don't fit into the regular scheme, like Bihari (bh, bih), or Serbo-Croatian (hbs).
• A last remark: The LoC's ISO 639-2 table doesn't supply any data to the Part2T column if the value is equal to Part2B. This has to be reflected in all queries dealing with this table.