/*
* !IMPORTANT! Please follow instructions at start of the file
diff --git a/src/box/sql/expr.c b/src/box/sql/expr.c
index ba7eea5..8cf4d2e 100644
--- a/src/box/sql/expr.c
+++ b/src/box/sql/expr.c
@@ -2958,28 +2958,22 @@ sqlCodeSubselect(Parse * pParse, /* Parsing context */
* Expr pIn is an IN(...) expression. This function checks that the
* sub-select on the RHS of the IN() operator has the same number of
* columns as the vector on the LHS. Or, if the RHS of the IN() is not
- * a sub-query, that the LHS is a vector of size 1.
+ * a sub-query, that the LHS must be a vector of size 1.

What is the point of changing this comment?

In SQlite it wasn't possible to write something like
"SELECT (1,2) in ..." so if length of the vector were more
than 1 it means it was received using subselect. It isn't
so in our case since we can work with such statements.
To emphasize this, I changed the comment.

New patch:

From 32b665f9ad9dacc16a492c55396dd843f9a355e9 Mon Sep 17 00:00:00 2001
Date: Sat, 18 May 2019 13:15:58 +0300
Subject: [PATCH] sql: rework SQL errors of type "expected column count"

Before this patch, errors of type "expected column count" were
divided into several different errors, and they all had an
ER_SQL_PARSER_GENERIC error code. This patch creates a new error
code for these errors.

In addition, at some point it became possible to use vectors as
the left value in the IN operator. Since this was previously
impossible, it led to a segmentation error.