[tarantool-patches] Re: [PATCH 1/2] sql: fix collation node duplication in AST

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

Hello, thanks for the review.

> On Jun 2, 2019, at 8:09 PM, Vladislav Shpilevoy <v.shpilevoy@tarantool.org> wrote:
> 
> Hi! Thanks for the fixes! See 2 comments below.
> 
> On 28/05/2019 17:10, Roman Khabibov wrote:
>> Hi! Thanks for the review.
>> 
>>> I vote for the second as the simplest, and add a test provided by me
>>> above to ensure we will never break it accidentally.
>>> 
>>> This commit should consist of the test and a comment in resolveAlias.
>>> And keep this nice ASCII schema.
>> 
>> diff --git a/src/box/sql/resolve.c b/src/box/sql/resolve.c
>> index 504096e6d..f952d8c04 100644
>> --- a/src/box/sql/resolve.c
>> +++ b/src/box/sql/resolve.c
>> @@ -109,6 +109,11 @@ resolveAlias(Parse * pParse,	/* Parsing context */
>> 		return;
>> 	if (zType[0] != 'G')
>> 		incrAggFunctionDepth(pDup, nSubquery);
>> +	/*
>> +	 * If there was typed more than one explicit collations in
>> +	 * query, it will be a sequence of left nodes with the
>> +	 * collations in a tree.
>> +	 */
> 
> 1. Please, add a comment, that there is nothing special about
> keeping the sequence. Only one collation could be stored, but
> the present solution is simpler.
diff --git a/src/box/sql/resolve.c b/src/box/sql/resolve.c
index 504096e6d..30b9bd9d6 100644
--- a/src/box/sql/resolve.c
+++ b/src/box/sql/resolve.c
@@ -109,6 +109,13 @@ resolveAlias(Parse * pParse,	/* Parsing context */
 		return;
 	if (zType[0] != 'G')
 		incrAggFunctionDepth(pDup, nSubquery);
+	/*
+	 * If there was typed more than one explicit collations in
+	 * query, it will be a sequence of left nodes with the
+	 * collations in a tree. There is nothing special about
+	 * keeping the sequence. Only one collation could be
+	 * stored, but the present solution is simpler.
+	 */
 	if (pExpr->op == TK_COLLATE) {
 		pDup =
 		    sqlExprAddCollateString(pParse, pDup, pExpr->u.zToken);

>> 	if (pExpr->op == TK_COLLATE) {
>> 		pDup =
>> 		    sqlExprAddCollateString(pParse, pDup, pExpr->u.zToken);
>> diff --git a/test/sql-tap/collation.test.lua b/test/sql-tap/collation.test.lua
>> index 0bf54576d..3c5d3053a 100755
>> --- a/test/sql-tap/collation.test.lua
>> +++ b/test/sql-tap/collation.test.lua
>> @@ -529,4 +529,21 @@ test:do_catchsql_test(
>>         'CREATE TABLE test3 (a int, b int, c int, PRIMARY KEY (a, a COLLATE foo, b, c))',
>>         {1, "Collation 'FOO' does not exist"})
>> 
>> +-- gh-3805 Check that collation is not ignored. Must pass.
> 
> 2. Of course it must pass. It is the purpose of test. Please,
> drop 'Must pass’.
Removed.

commit c409d222c500ef2b355d0c4061a3931aa6374780
Author: Roman Khabibov <roman.habibov@tarantool.org>
Date:   Mon May 6 14:45:51 2019 +0300

    test: check that collations isn't ignored in SELECTs
    
    Add test to check that a new collation isn't ignored regardless
    of a name of a previous one in the following patterns of quries:
    
    SELECT s COLLATE "unicode_ci" FROM a ORDER BY s COLLATE "unicode_ci"
    
    Also note: It is disallowed to compare strings with different
    collations: ISO/IEC JTC 1/SC 32, Part 2: Foundation, page 531

diff --git a/src/box/sql/resolve.c b/src/box/sql/resolve.c
index 504096e6d..30b9bd9d6 100644
--- a/src/box/sql/resolve.c
+++ b/src/box/sql/resolve.c
@@ -109,6 +109,13 @@ resolveAlias(Parse * pParse,	/* Parsing context */
 		return;
 	if (zType[0] != 'G')
 		incrAggFunctionDepth(pDup, nSubquery);
+	/*
+	 * If there was typed more than one explicit collations in
+	 * query, it will be a sequence of left nodes with the
+	 * collations in a tree. There is nothing special about
+	 * keeping the sequence. Only one collation could be
+	 * stored, but the present solution is simpler.
+	 */
 	if (pExpr->op == TK_COLLATE) {
 		pDup =
 		    sqlExprAddCollateString(pParse, pDup, pExpr->u.zToken);
diff --git a/test/sql-tap/collation.test.lua b/test/sql-tap/collation.test.lua
index 0bf54576d..9d0076e1d 100755
--- a/test/sql-tap/collation.test.lua
+++ b/test/sql-tap/collation.test.lua
@@ -1,6 +1,6 @@
 #!/usr/bin/env tarantool
 test = require("sqltester")
-test:plan(174)
+test:plan(177)
 
 local prefix = "collation-"
 
@@ -529,4 +529,21 @@ test:do_catchsql_test(
         'CREATE TABLE test3 (a int, b int, c int, PRIMARY KEY (a, a COLLATE foo, b, c))',
         {1, "Collation 'FOO' does not exist"})
 
+-- gh-3805 Check that collation is not ignored.
+
+test:do_execsql_test(
+    "collation-2.6.0",
+    [[ CREATE TABLE a (id INT PRIMARY KEY, s TEXT) ]],
+    {})
+
+test:do_execsql_test(
+    "collation-2.6.1",
+    [[ INSERT INTO a VALUES (1, 'B'), (2, 'b') ]],
+    {})
+
+test:do_execsql_test(
+    "collation-2.6.2",
+    [[ SELECT s COLLATE "unicode_ci" FROM a ORDER BY s COLLATE "unicode" ]],
+    {"b","B"})
+
 test:finish_test()