docs: update README and comments

README.md

@@ -6,74 +6,17 @@ A tiny and dummy database built by myself.
 
 
 
-## Introdution
+## Introduction
 
 This project is inspired by sqlite, has a similar architecture with sqlite (but simpler).
 
 <img src = "./docs/img/sqlite.png" style = "width: 40%" />
 
 - `tinydb` is the simplest prototype of database, it only contains **ONE** table (see `table_t` and `row_t` in source file `types.h`), whose schema is `id(uint32_t), username(string), email(string)` .
 - `id(int)` is the primary key of our table, we will implement index via B+Tree.
+- `sqlparser-main.c` - The entry of tinydb. In this program, I implement an tiny SQL Parser based on Flex & Bison, thus the SQL statements in this program are mostly like sqlite or MySQL. And it supports `where` conditions.
 
-
-There are two version of `tinydb`:
-
-- `main.c` - In this program, I parse the SQL statements by spliting strings, thus the SQL statements are incomplete. And it does **NOT** support `where` keyword.
-- `main2.c` - In this program, I implement an tiny SQL Parser based on Flex & Bison, thus the SQL statements in this program are mostly like sqlite or MySQL. And it supports `where` conditions.
-
-For both of them, they have the same format of database file.
-
-
-
-## Build `main.c`
-
-This project has only one `.c` file. And you can build it by:
-
-```text
-make dummy
-./tinydb mydb.db
-```
-
-And it will enter our REPL (Read, Evaluate, Print, Loop) program:
-
-```text
-tinydb > insert 1 1 1
-Executed.
-tinydb > insert 2 2 2
-Executed.
-tinydb > insert 3 3 3
-Executed.
-tinydb > update 1 a a
-Executed.
-tinydb > delete 3
-Executed.
-tinydb > select
-(1, a, a)
-(2, 2, 2)
-total 2 rows
-Executed.
-tinydb > 
-```
-
-From so far, `tinydb` supports these sql statement:
-
-- `insert`
-- `select`
-- `delete`
-- `update`
-- `commit`
-- `rollback`
-
-And it also support some meta commands (for debugging):
-
-- `.help`
-- `.exit`
-- `.constants`
-- `.btree`
-
-
-
-## Build `main2.c`
+## Build `sqlparser-main.c`
 
 ```bash
 make build
@@ -92,7 +35,7 @@ In this program, I implement a SQL Parser. It will support SQL statements like:
 - `COMMIT;`
 - `ROLLBACK;`
 
-For the above keywords, we can also use lower cases: `select, insert, delete, update, ...`
+For the above keywords, they can be lower cases: `select, insert, delete, update, ...`
 
 Please note that there is a `';'` after each SQL statement.
 
@@ -138,7 +81,7 @@ Running this testing script, will fill the database file `mydb.db` with dummy da
 
 
 
-## Recommend Readings
+## Further Reading
 
 - [1] [SQLite Database System: Design and Implementation](https://play.google.com/store/books/details/SQLite_Database_System_Design_and_Implementation_F?id=9Z6IQQnX1JEC&gl=US)
 - [2] [Architecture of SQLite](https://www.sqlite.org/arch.html)

main.c

@@ -1,3 +1,13 @@
+/* In this main.c, I implement the REPL by splitting the string (e.g. strtok, strcmp).
+ * It only support SQL statements as following:
+ * 1) insert 1 1 1 (Insert one row into the table.)
+ * 2) update 1 a a (Update one row where id = 1.)
+ * 3) delete 3     (Delete one row where id = 3.)
+ * 4) select       (Print all rows in table.)
+ * 5) commit       (Commit all dirty pages in memory.)
+ * 6) rollback     (Rollback ONE operation.)
+ * This file is deprecated, since we have more advanced SQL parser, see sqlparser-main.c
+ */
 #include "common.h"
 #include "dummyparser.h"
 #include "transaction.h"
@@ -29,11 +39,7 @@ int main(int argc, char *argv[])
             }
         }
 
-        statement_t statement = {
-            .conditions = NULL,
-            .schemas = NULL,
-            .table_name = filename
-        };
+        statement_t statement = {.conditions = NULL, .schemas = NULL, .table_name = filename};
         switch (parse_statement(input_buffer, &statement))
         {
         case PARSE_SUCCESS:

makefile

@@ -9,7 +9,7 @@ DBKERNEL=$(PROJECT)/db-kernel
 INCLUDE=-I$(PROJECT) -I$(SQLPARSER) -I$(SQLVM) -I$(LIBS) -I$(DBKERNEL)
 
 build: sqlparser
-	$(CC) $(INCLUDE) sqlparser.tab.c lex.yy.c main2.c -o tinydb
+	$(CC) $(INCLUDE) sqlparser.tab.c lex.yy.c sqlparser-main.c -o tinydb
 
 clean:
 	rm *.db tinydb lex.yy.c *.tab.c *.tab.h