Hello! Thank you for review! New patch below. There won't be diff
between versions as I started this version before decided to save
this diff.

Hi! Thanks for the patch!

I see that Kostja slightly reviewed it and you did not
answer him, so I inlined here some of his comments to
agree/disagree with them.

See 8 comments below.

On 28/09/2018 19:53, imeevma@tarantool.org wrote:

According to documentation some JDBC functions have an ability to
return all ids that were generated in executed INSERT statement.
This patch gives a way to implement such functionality.

Closes #2618
---
Branch: https://github.com/tarantool/tarantool/tree/imeevma/gh-2618-return-all-generated-ids
Issue: https://github.com/tarantool/tarantool/issues/2618

  src/box/execute.c        | 24 ++++++++++++++++
  src/box/execute.h        |  1 +
  src/box/lua/net_box.c    | 21 ++++++++++++--
  src/box/sequence.c       | 29 ++++++++++++++++++++
  src/box/sql/vdbe.c       |  2 +-
  src/box/sql/vdbe.h       |  3 +-
  src/box/sql/vdbeInt.h    |  3 ++
  src/box/sql/vdbeaux.c    | 15 ++++++++--
  src/box/txn.h            | 13 +++++++++
  test/sql/iproto.result   | 71 ++++++++++++++++++++++++++++++++++++++++++++++++
  test/sql/iproto.test.lua | 15 ++++++++++
  11 files changed, 190 insertions(+), 7 deletions(-)

diff --git a/src/box/execute.c b/src/box/execute.c
index 24459b4..d9fe33f 100644
--- a/src/box/execute.c
+++ b/src/box/execute.c
@@ -42,6 +42,7 @@
  #include "schema.h"
  #include "port.h"
  #include "tuple.h"
+#include "sql/vdbeInt.h"

1. Kostja said:

Ugh. You're including a header which ends with Int. Have you
thought what this Int means? It's not Integer.

Strictly speaking, I agree with him. Src/box/execute is not
an SQL internal file. It even uses SQLite public API to
fetch names and types. I guess, you should implement a getter
for ids list like

    const struct stailq *
    vdbe_auto_ids_list(const struct Vdbe *v);

    const char *sql_type_strs[] = {
      NULL,
@@ -639,14 +640,37 @@ err:
          assert(port_tuple->size == 0);
          if (iproto_reply_map_key(out, 1, IPROTO_SQL_INFO) != 0)
              goto err;
+        struct stailq *id_list = &((struct Vdbe *)stmt)->id_list;
+        uint64_t id_count = 0;
          int changes = sqlite3_changes(db);
          int size = mp_sizeof_uint(SQL_INFO_ROW_COUNT) +
                 mp_sizeof_uint(changes);
+        if (stailq_empty(id_list) == 0) {

2. Kostja said:

What is the point of this == 0? Why are you comparing with an
integer here, not boolean?

I partially agree and I guess it is my fault that I am too harsh
about code style. You used here == 0 because stailq_empty()
returns an integer, but its name looks like a flag getter, so you
can use it as a boolean here.

+            struct id_entry *id_entry;
+            stailq_foreach_entry(id_entry, id_list, link) {
+                size += id_entry->id >= 0 ?
+                    mp_sizeof_uint(id_entry->id) :
+                    mp_sizeof_int(id_entry->id);
+                id_count++;
+            }
+            size += mp_sizeof_uint(SQL_INFO_GENERATED_IDS) +
+                mp_sizeof_array(id_count);
+        }>           char *buf = obuf_alloc(out, size);
          if (buf == NULL) {
              diag_set(OutOfMemory, size, "obuf_alloc", "buf");
              goto err;
          }
+        if (id_count > 0) {

3. Lets be consistent: either you use !stailq_empty() in both
places, or id_count > 0.

+            buf = mp_encode_uint(buf, SQL_INFO_GENERATED_IDS);
+            buf = mp_encode_array(buf, id_count);
+            struct id_entry *id_entry;
+            stailq_foreach_entry(id_entry, id_list, link) {
+                buf = id_entry->id >= 0 ?
+                      mp_encode_uint(buf, id_entry->id) :
+                      mp_encode_int(buf, id_entry->id);
+            }
+        }
          buf = mp_encode_uint(buf, SQL_INFO_ROW_COUNT);
          buf = mp_encode_uint(buf, changes);
      }
diff --git a/src/box/lua/net_box.c b/src/box/lua/net_box.c
index a928a4c..5d2ac78 100644
--- a/src/box/lua/net_box.c
+++ b/src/box/lua/net_box.c
@@ -671,11 +671,28 @@ netbox_decode_sql_info(struct lua_State *L, const char **data)
      /* Only SQL_INFO_ROW_COUNT is available. */
      assert(map_size == 1);

4. How does it work? map_size can be 2 now, and the comment is
outdated - not only SQL_INFO_ROW_COUNT is available.

      (void) map_size;
+    lua_newtable(L);
      uint32_t key = mp_decode_uint(data);
+    /*
+     * If SQL_INFO_GENERATED_IDS in data then it should be
+     * just before SQL_INFO_ROW_COUNT.
+     */
+    if (key == SQL_INFO_GENERATED_IDS) {
+        uint64_t count = mp_decode_array(data);
+        assert (count > 0);
+        lua_createtable(L, 0, count);
+        lua_setfield(L, -2, "generated_ids");
+        lua_getfield(L, -1, "generated_ids");
+        for (uint32_t j = 0; j < count; ++j) {
+            int64_t value = mp_decode_uint(data);
+            lua_pushinteger(L, value);
+            lua_rawseti(L, -2, j + 1);
+        }
+        lua_pop(L, 1);
+        key = mp_decode_uint(data);
+    }
      assert(key == SQL_INFO_ROW_COUNT);
-    (void) key;
      uint32_t row_count = mp_decode_uint(data);
-    lua_createtable(L, 0, 1);
      lua_pushinteger(L, row_count);
      lua_setfield(L, -2, "rowcount");
  }
diff --git a/src/box/sequence.c b/src/box/sequence.c
index 35b7605..ed6b2da 100644
--- a/src/box/sequence.c
+++ b/src/box/sequence.c
@@ -38,6 +38,7 @@
  #include <small/mempool.h>
  #include <msgpuck/msgpuck.h>
  +#include "txn.h"
  #include "diag.h"
  #include "error.h"
  #include "errcode.h"
@@ -178,6 +179,30 @@ sequence_update(struct sequence *seq, int64_t value)
      return 0;
  }
  +/**
+ * Save generated id in VDBE.
+ *
+ * @param value ID to save in VDBE.
+ * @retval 0 Success.
+ * @retval -1 Error.
+ */
+static inline int
+add_new_id_in_vdbe(int64_t value)

5. Kostja said:

subject-verb-object

I agree. He means 'vdbe_add_new_id'. And in such a
case it is evidently a part of Vdbe API, so put it into
vdbe.h with this signature:

    int
    vdbe_add_new_auto_id(struct Vdbe *vdbe, int64_t id);

+{
+    struct txn *txn = in_txn();
+    if (txn == NULL || txn->psql_txn == NULL)
+        return 0;
+    assert(txn->psql_txn->vdbe != NULL);
+    struct id_entry *id_entry = malloc(sizeof(*id_entry));
+    if (id_entry == NULL) {
+        diag_set(OutOfMemory, sizeof(*id_entry), "malloc", "id_entry");
+        return -1;
+    }
+    id_entry->id = value;
+    stailq_add_tail_entry(txn->psql_txn->id_list, id_entry, link);

6. If you have Vdbe, you do not need to store the list both in
Vdbe and sql_txn. Store it in Vdbe only.

7. Kostja said:

Why malloc?

It is understandable why malloc - txn after commit invalidates
the region memory. We neither can save ids on obuf directly
since while getting next id a yield is possible and the obuf
will be messed with another request.  But guess I thought up a
solution. It is a bit tricky, so maybe it should be accounted
as a separate issue and this solved with malloc.

I propose to split txn_commit() into commit and region reset.
Txn_commit() goal is to write data to disk, not to destroy a
region. It saves us when a transaction is started and committed
by Vdbe. But what about autocommit transactions? I think, we
should get rid of autocommit transactions for Vdbe. Vdbe always
starts a transaction for DML and commits it, but without region
reset - it is a part of vdbe finalize routine (which already
exists actually).

This split of txn_commit logic allows to store anything on
a region during Vdbe work and not being afraid about a reset.

+    return 0;
+}
+
diff --git a/src/box/sql/vdbe.h b/src/box/sql/vdbe.h
index d5da5d5..9b94183 100644
--- a/src/box/sql/vdbe.h
+++ b/src/box/sql/vdbe.h
@@ -179,10 +179,11 @@ Vdbe *sqlite3VdbeCreate(Parse *);
   * Allocate and initialize SQL-specific struct which completes
   * original Tarantool's txn struct using region allocator.
   *
+ * @param vdbe VDBE that is being prepared or executed.
   * @retval NULL on OOM, new psql_txn struct on success.
   **/
  struct sql_txn *
-sql_alloc_txn();
+sql_alloc_txn(struct Vdbe *vdbe);

8. I think, alloc should only alloc. sql_txn_begin should
put Vdbe into sql_txn.