Re: Create New Data Type

[larry williams]

In order to create a new data type, you need to be familiar with both the sql_yacc.yy and the lex.h files. Understanding these files, how they are converted into sql_yacc.cc, sql_yacc.h and lex_hash.h is critical, but not the point of this response. Understanding these files and how to use them is the first step. I am starting with 'step 2'.

In sql_yacc:

Add a 'token' for your data type. Notice that the token list is alphabetical. Keep it this way.
%token MYTYPE /* LRW TYPE */

In the '%type <NONE>' section, add the reference for your new data type. I admit that I do not understand this section and its purpose, but I needed include my type here. Notice that there are other 'non-base' data type declarations here too.

ref_list opt_match_clause opt_on_update_delete use
--> mytype opt_delete_options opt_delete_option varchar
nchar nvarchar opt_outer table_list table_name
table_alias_ref_list