Update SQL IPROTO codes

[Gerold103]

After tarantool/tarantool@43e03e6 IPROTO_FIELD_NAME has code 0 instead of 0x29.

[lenkis]

To be documented when this RFC is fully implemented:
https://github.com/tarantool/tarantool/blob/gh-3328-new-iproto/doc/rfc/3328-wire_protocol.md

At that point we'll need to add new info to "Internals":

(1) universal response packet structure (sent in response to both SQL and non-SQL queries) that will contain new fields:

+----------------------------------------------+
| IPROTO_BODY: {                               |
|     IPROTO_METADATA: [                       |
|         {                                    |
|             IPROTO_FIELD_NAME: string,       |
|             IPROTO_FIELD_TYPE: number,       |
|             IPROTO_FIELD_FLAGS: number,      |
|         },                                   |
|         ...                                  |
|     ],                                       |
|                                              |
|     IPROTO_SQL_INFO: {                       |
|         SQL_INFO_ROW_COUNT: number,          |
|         SQL_INFO_LAST_ID: number,            |
|         ...                                  |
|     },                                       |
|                                              |
|     IPROTO_DATA: [                           |
|         tuple/scalar,                        |
|         ...                                  |
|     ]                                        |
| }                                            |
+----------------------------------------------+

New fields are: IPROTO_METADATA with nested fields + IPROTO_SQL_INFO with nested fields.

(2) example of a multi-packet response to SQL queries
Query example:

FUNCTION my_sql_func(a1, a2, a3, a4) BEGIN
    SELECT my_lua_func(a1);
    SELECT * FROM table1;
    SELECT my_c_func(a2);
    INSERT INTO table1 VALUES (1, 2, 3);
    RETURN a4;
END

Response example (split into several packets if SQL reply data is too big):

/* Push from my_lua_func(a1). */
+----------------------------------------------+
| HEADER: IPROTO_CHUNK                         |
+- - - - - - - - - - - - - - - - - - - - - - - +
| BODY: {                                      |
|     IPROTO_DATA: [ a1 ]                      |
| }                                            |
+----------------------------------------------+

/* Result of SELECT my_lua_func(a1). */
+----------------------------------------------+
| HEADER: IPROTO_CHUNK                         |
+- - - - - - - - - - - - - - - - - - - - - - - +
| BODY: {                                      |
|     IPROTO_DATA: [ [ a1 ] ],                 |
|     IPROTO_METADATA: [                       |
|         { /* field name, type ... */ }       |
|     ]                                        |
| }                                            |
+----------------------------------------------+

/* First chunk of SELECT * FROM table1. */
+----------------------------------------------+
| HEADER: IPROTO_CHUNK, IPROTO_CHUNK_ID = <id1>|
+- - - - - - - - - - - - - - - - - - - - - - - +
| BODY: {                                      |
|    IPROTO_DATA: [ tuple1, tuple2, ... ]      |
|    IPROTO_METADATA: [                        |
|        { /* field1 name, type ... */ },      |
|        { /* field2 name, type ... */ },      |
|        ...                                   |
|    ]                                         |
| }                                            |
+----------------------------------------------+

        /* From second to next to last chunk. */
	+----------------------------------------------+
	| HEADER: IPROTO_CHUNK, IPROTO_CHUNK_ID = <id1>|
	+- - - - - - - - - - - - - - - - - - - - - - - +
	| BODY: {                                      |
	|    IPROTO_DATA: [ tuple1, tuple2, ... ]      |
	| }                                            |
	+----------------------------------------------+

	/* Last chunk. */
	+----------------------------------------------+
	| HEADER: IPROTO_CHUNK, IPROTO_CHUNK_ID = <id1>|
	+- - - - - - - - - - - - - - - - - - - - - - - +
	| BODY: {                                      |
	|    IPROTO_DATA: [ tuple1, tuple2, ... ]      |
	| }                                            |
	+----------------------------------------------+

/* Result of SELECT my_c_func(a2). */
+----------------------------------------------+
| HEADER: IPROTO_CHUNK                         |
+- - - - - - - - - - - - - - - - - - - - - - - +
| BODY: {                                      |
|     IPROTO_DATA: [ [ tuple ] ],              |
|     IPROTO_METADATA: [                       |
|         { /* field name, type ... */ }       |
|     ]                                        |
| }                                            |
+----------------------------------------------+

/* Result of INSERT INTO table1 VALUES (1, 2, 3). */
+----------------------------------------------+
| HEADER: IPROTO_CHUNK                         |
+- - - - - - - - - - - - - - - - - - - - - - - +
| BODY: {                                      |
|     IPROTO_SQL_INFO: {                       |
|         SQL_INFO_ROW_COUNT: number,          |
|         SQL_INFO_LAST_ID: number,            |
|     }                                        |
| }                                            |
+----------------------------------------------+

/* Result of RETURN a4 */
+----------------------------------------------+
| HEADER: IPROTO_OK                            |
+- - - - - - - - - - - - - - - - - - - - - - - +
| BODY: {                                      |
|     IPROTO_DATA: [ a4 ]                      |
| }                                            |
+----------------------------------------------+

(3) state machine diagram: https://github.com/tarantool/tarantool/blob/gh-3328-new-iproto/doc/rfc/3328-wire_protocol_img1.svg

[Gerold103]

Please, update the link to the state machine image - I have uploaded svg instead of png right now.

[lenkis]

done

[Totktonada]

Note: We have SQL_INFO_AUTOINCREMENT_IDS instead of SQL_INFO_LAST_ID now.

[Totktonada]

It seems it is done.

[lenkis]

@veod32 please double-check what is done and add everything what is still missing