SQLite

used to generate that documentation are in a separate source repository.

The SQL language parser is **parse.c** which is generate from a grammar in
the src/parse.y file.  The conversion of "parse.y" into "parse.c" is done
by the [lemon](./doc/lemon.html) LALR(1) parser generator.  The source code
for lemon is at tool/lemon.c.  Lemon uses the tool/lempar.c file as a
template for generating its parser.

Lemon also generates the **parse.h** header file, at the same time it
generates parse.c. But the parse.h header file is
modified further (to add additional symbols) using the ./addopcodes.tcl
Tcl script.

The **opcodes.h** header file contains macros that define the numbers
corresponding to opcodes in the "VDBE" virtual machine.  The opcodes.h
file is generated by the scanning the src/vdbe.c source file.  The
Tcl script at ./mkopcodeh.tcl does this scan and generates opcodes.h.
A second Tcl script, ./mkopcodec.tcl, then scans opcodes.h to generate
the **opcodes.c** source file, which contains a reverse mapping from

columnlist ::= columnname carglist.
columnname(A) ::= nm(A) typetoken(Y). {sqlite3AddColumn(pParse,&A,&Y);}

// Declare some tokens early in order to influence their values, to 
// improve performance and reduce the executable size.  The goal here is
// to get the "jump" operations in ISNULL through ESCAPE to have numeric
// values that are early enough so that all jump operations are clustered
// at the beginning, but also so that the comparison tokens NE through GE
// are as large as possible so that they are near to FUNCTION, which is a
// token synthesized by addopcodes.tcl.
//
%token ABORT ACTION AFTER ANALYZE ASC ATTACH BEFORE BEGIN BY CASCADE CAST.
%token CONFLICT DATABASE DEFERRED DESC DETACH EACH END EXCLUSIVE EXPLAIN FAIL.
%token OR AND NOT IS MATCH LIKE_KW BETWEEN IN ISNULL NOTNULL NE EQ.
%token GT LE LT GE ESCAPE.

// The following directive causes tokens ABORT, AFTER, ASC, etc. to