[tarantool-patches] Re: [PATCH] sql: refactor SQL cursor to remove write ones

["n.pettik" <korablev@tarantool.org>]

> Hello Nikita!
> Thanks for review. All nits applied.
> Updated patch in the bottom. Branch force-pushed.

IDK whether it is outlined in our review policy or not, but it is quite
hard to review each time the whole patch again. So, it would be nice
if you attached intermediate diff (i.e. diff between two versions of patch)
in order to review only parts which have changed. Or, inline diff for
each comment/remark.

>>>> Finally, now I think about renaming CursorOpen to IteratorOpen: in fact after your
>>>> patch cursor has turned almost in wrapper around index iterator. Such naming
>>>> would underline the fact that ‘cursor’ is used only for read iterations over the space.
>>> Yes, sure. Renamed.
>> 
>> You forgot to update name of opcode in commit message.
>> Also, you deleted not all mentions of OP_Cursor(Re)Open - just grep it

Still, I can grep OP_OpenWrite. Eliminate it completely pls.

Consider code style fixes:

diff --git a/src/box/sql/select.c b/src/box/sql/select.c
index 929d3c814..353b0af9f 100644
--- a/src/box/sql/select.c
+++ b/src/box/sql/select.c
@@ -86,7 +86,7 @@ struct SortCtx {
        ExprList *pOrderBy;     /* The ORDER BY (or GROUP BY clause) */
        int nOBSat;             /* Number of ORDER BY terms satisfied by indices */
        int iECursor;           /* Cursor number for the sorter */
-       /* Register, containing pointer to ephemeral space. */
+       /** Register, containing pointer to ephemeral space. */
        int reg_eph;
        int regReturn;          /* Register holding block-output return address */
        int labelBkOut;         /* Start label for the block-output subroutine */
@@ -1005,7 +1005,8 @@ selectInnerLoop(Parse * pParse,           /* The parser context */
                                regPrev = pParse->nMem + 1;
                                pParse->nMem += nResultCol;
 
-                               /* Actually, for DISTINCT handling
+                               /*
+                                * Actually, for DISTINCT handling
                                 * two op-codes were emitted here:
                                 * OpenTEphemeral & IteratorOpen.
                                 * So, we need to Noop one and
@@ -1061,7 +1062,7 @@ selectInnerLoop(Parse * pParse,           /* The parser context */
                        }
 
                case WHERE_DISTINCT_UNIQUE:{
-                       /**
+                       /*
                         * To handle DISTINCT two op-codes are
                         * emitted: OpenTEphemeral & IteratorOpen.
                         * addrTnct is address of first insn in

Except for these nits, patch LGTM.