Localization

A column marked as Loc is actually 17 columns with one column per language and a bitmask in the end.

There can be multiple languages filled in -- i.e. multi-language DBCs are possible.

Blizzard no longer uses multiple columns for Localization since Cataclysm. From there on, there just is one column with a string in the language given by the locale directory. This conserves space and prevents errors with missing locale data as present on a lot of modded servers, where a locale_i DBC is taken and edited, packed and distributed, therefore resulting in empty strings for all clients not using locale_i. In Cataclysm and up, there just will be wrong language strings.

Number of columns actually varies depending on client version. The information how to read a particular structure is given [here]

Column		Field
0	enUS / enGB	English US / English GB
1	koKR	Korean
2	frFR	French
3	deDE	German
4	zhCN	Chinese
5	zhTW	Taiwan
6	esES	Spanish (Spain)
7	esMX	Spanish (Mexican)
8	ruRU	Russian
9	jaJP	Japanese
10	ptPT	Portuguese. Also ptBR
11	itIT	Italian
12	unused1	Unused
13	unused2	Unused
14	unused2	Unused
15	flags	BitMask that always follows the string fields. Never read by the client.

Russian was added in TBC, Portugese and Italian were added in WotLK

struct langstringref
{
#if < 
  stringref enUS;   // also enGB
  stringref koKR;
  stringref frFR;
  stringref deDE;
  stringref enCN;   // also zhCN
  stringref enTW;   // also zhTW
  stringref esES;
  stringref esMX;
//! \todo verify that pre->8 locales hadn't changed
#if ≥  (2.1.0.6692)
  stringref ruRU;
  stringref jaJPᵘ; // unknowns are still unused as of 8.0.1.26095
  stringref ptPT;   // also ptBR
  stringref itIT;
  stringref unknown_12;
  stringref unknown_13;
  stringref unknown_14;
  stringref unknown_15;
#endif
  uint32_t flags;
#else
  stringref client_locale;
#endif
};