[Tarantool-patches] [PATCH] sql: display collation in metadata for scalar

[Roman Khabibov <roman.habibov@tarantool.org>]

Fix bug with the  display of collation for scalar fields in
<SELECT> result, when sql_full_metadata is enabled.

Closes #4755
---
Branch: https://github.com/tarantool/tarantool/tree/romanhabibov/gh-4755-scalar-collation
Issue: https://github.com/tarantool/tarantool/issues/4755

@ChangeLog
- Fix bug with no collation display for scalar fields in <SELECT>
when sql_full_metadata is enabled.

 src/box/sql/select.c                          |  7 ++-
 .../gh-4755-scalar-collation-metadata.result  | 56 +++++++++++++++++++
 ...gh-4755-scalar-collation-metadata.test.lua | 22 ++++++++
 3 files changed, 82 insertions(+), 3 deletions(-)
 create mode 100644 test/sql/gh-4755-scalar-collation-metadata.result
 create mode 100755 test/sql/gh-4755-scalar-collation-metadata.test.lua

diff --git a/src/box/sql/select.c b/src/box/sql/select.c
index f39484013..92d20e992 100644
--- a/src/box/sql/select.c
+++ b/src/box/sql/select.c
@@ -1792,9 +1792,10 @@ generate_column_metadata(struct Parse *pParse, struct SrcList *pTabList,
 			continue;
 		if (p->op == TK_VARIABLE)
 			var_pos[var_count++] = i;
-		vdbe_metadata_set_col_type(v, i,
-					   field_type_strs[sql_expr_type(p)]);
-		if (is_full_meta && sql_expr_type(p) == FIELD_TYPE_STRING) {
+		enum field_type type = sql_expr_type(p);
+		vdbe_metadata_set_col_type(v, i, field_type_strs[type]);
+		if (is_full_meta && (type == FIELD_TYPE_STRING ||
+		    type == FIELD_TYPE_SCALAR)) {
 			bool unused;
 			uint32_t id = 0;
 			struct coll *coll = NULL;
diff --git a/test/sql/gh-4755-scalar-collation-metadata.result b/test/sql/gh-4755-scalar-collation-metadata.result
new file mode 100644
index 000000000..2ffcc79f3
--- /dev/null
+++ b/test/sql/gh-4755-scalar-collation-metadata.result
@@ -0,0 +1,56 @@
+-- test-run result file version 2
+env = require('test_run')
+ | ---
+ | ...
+test_run = env.new()
+ | ---
+ | ...
+
+--
+-- gh-4755: Collation in metadata must be displayed as for string
+-- filed as for scalar field.
+--
+test_run:cmd("setopt delimiter ';'");
+ | ---
+ | - true
+ | ...
+box.execute([[UPDATE "_session_settings"
+                  SET "value" = true
+                  WHERE "name" = 'sql_full_metadata';]]);
+ | ---
+ | - row_count: 1
+ | ...
+box.execute([[CREATE TABLE test (a SCALAR COLLATE "unicode_ci" PRIMARY KEY,
+                                 b STRING COLLATE "unicode_ci");]]);
+ | ---
+ | - row_count: 1
+ | ...
+box.execute("SELECT * FROM test;");
+ | ---
+ | - metadata:
+ |   - span: A
+ |     type: scalar
+ |     is_nullable: false
+ |     name: A
+ |     collation: unicode_ci
+ |   - span: B
+ |     type: string
+ |     is_nullable: true
+ |     name: B
+ |     collation: unicode_ci
+ |   rows: []
+ | ...
+
+--
+-- Cleanup.
+--
+box.execute([[UPDATE "_session_settings"
+                  SET "value" = false
+                  WHERE "name" = 'sql_full_metadata';]]);
+ | ---
+ | - row_count: 1
+ | ...
+box.execute("DROP TABLE test;");
+ | ---
+ | - row_count: 1
+ | ...
diff --git a/test/sql/gh-4755-scalar-collation-metadata.test.lua b/test/sql/gh-4755-scalar-collation-metadata.test.lua
new file mode 100755
index 000000000..197b06891
--- /dev/null
+++ b/test/sql/gh-4755-scalar-collation-metadata.test.lua
@@ -0,0 +1,22 @@
+env = require('test_run')
+test_run = env.new()
+
+--
+-- gh-4755: Collation in metadata must be displayed as for string
+-- filed as for scalar field.
+--
+test_run:cmd("setopt delimiter ';'");
+box.execute([[UPDATE "_session_settings"
+                  SET "value" = true
+                  WHERE "name" = 'sql_full_metadata';]]);
+box.execute([[CREATE TABLE test (a SCALAR COLLATE "unicode_ci" PRIMARY KEY,
+                                 b STRING COLLATE "unicode_ci");]]);
+box.execute("SELECT * FROM test;");
+
+--
+-- Cleanup.
+--
+box.execute([[UPDATE "_session_settings"
+                  SET "value" = false
+                  WHERE "name" = 'sql_full_metadata';]]);
+box.execute("DROP TABLE test;");
-- 
2.21.0 (Apple Git-122)