[Tarantool-patches] [PATCH v2 0/3] Add ability to drop constraints

[Tarantool-patches] [PATCH v2 0/3] Add ability to drop constraints

[Roman Khabibov]

@ChangeLog
- Add function space_index_by_name().
- Add ability to spacify searching index in OP_SDelete.
- Add function vdbe_emit_index_drop() to drop index by name.
- Remove box_index_by_name() from build.c and pragma.c.
- Rewrite function sql_drop_foreign_key() to  sql_drop_constraint().
- Add ability to drop all the types of constraints.
- Modify "no such constrait" error message.

Hello, everybody!
As Nikita requested, I performed the patch to remove
box_index_by_name() from build.c and pragma.c, but what about
analyze.c? Still had to add space_index_by_name() to use in
pragma.c, beacuse struct index is required.

Roman Khabibov (3):
  sql: improve "no such constraint" error message
  sql: don't select from _index during parsing
  sql: support constraint drop

 src/box/constraint_id.h      |   1 +
 src/box/errcode.h            |   2 +-
 src/box/space.h              |  15 ++++
 src/box/sql/alter.c          |   2 +-
 src/box/sql/build.c          | 143 ++++++++++++++++++++++-------------
 src/box/sql/parse.y          |   4 +-
 src/box/sql/parse_def.h      |  11 +--
 src/box/sql/pragma.c         |   8 +-
 src/box/sql/sqlInt.h         |   7 +-
 src/box/sql/vdbe.c           |  10 ++-
 test/sql-tap/alter2.test.lua |   2 +-
 test/sql/checks.result       |   2 +-
 test/sql/constraint.result   |  81 ++++++++++++++++++++
 test/sql/constraint.test.lua |  28 +++++++
 14 files changed, 240 insertions(+), 76 deletions(-)

-- 
2.21.0 (Apple Git-122)

[Tarantool-patches] [PATCH v2 1/3] sql: improve "no such constraint" error message

[Roman Khabibov]

Clarify the error message for better user handling. Add the name
of space where the constraint under dropping didn't founded.

Part of #4120
---
 src/box/errcode.h            |  2 +-
 src/box/sql/alter.c          |  2 +-
 src/box/sql/build.c          | 24 +++++++++++++-----------
 test/sql-tap/alter2.test.lua |  2 +-
 test/sql/checks.result       |  2 +-
 5 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/src/box/errcode.h b/src/box/errcode.h
index 6f6e28c6c..b7787d378 100644
--- a/src/box/errcode.h
+++ b/src/box/errcode.h
@@ -221,7 +221,7 @@ struct errcode_record {
 	/*166 */_(ER_NO_SUCH_COLLATION,		"Collation '%s' does not exist") \
 	/*167 */_(ER_CREATE_FK_CONSTRAINT,	"Failed to create foreign key constraint '%s': %s") \
 	/*168 */_(ER_DROP_FK_CONSTRAINT,	"Failed to drop foreign key constraint '%s': %s") \
-	/*169 */_(ER_NO_SUCH_CONSTRAINT,	"Constraint %s does not exist") \
+	/*169 */_(ER_NO_SUCH_CONSTRAINT,	"Constraint '%s' does not exist in space '%s'") \
 	/*170 */_(ER_CONSTRAINT_EXISTS,		"%s constraint '%s' already exists in space '%s'") \
 	/*171 */_(ER_SQL_TYPE_MISMATCH,		"Type mismatch: can not convert %s to %s") \
 	/*172 */_(ER_ROWID_OVERFLOW,            "Rowid is overflowed: too many entries in ephemeral space") \
diff --git a/src/box/sql/alter.c b/src/box/sql/alter.c
index 973b420cf..14f6c1a97 100644
--- a/src/box/sql/alter.c
+++ b/src/box/sql/alter.c
@@ -121,7 +121,7 @@ sql_alter_ck_constraint_enable(struct Parse *parse)
 	int addr = sqlVdbeAddOp4Int(v, OP_Found, cursor, 0, key_reg, 2);
 	sqlVdbeAddOp4(v, OP_SetDiag, ER_NO_SUCH_CONSTRAINT, 0, 0,
 		      sqlMPrintf(db, tnt_errcode_desc(ER_NO_SUCH_CONSTRAINT),
-				 constraint_name), P4_DYNAMIC);
+				 constraint_name, tbl_name), P4_DYNAMIC);
 	sqlVdbeAddOp2(v, OP_Halt, -1, ON_CONFLICT_ACTION_ABORT);
 	sqlVdbeJumpHere(v, addr);
 
diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index bc50ecbfa..d9bf8de91 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -1476,21 +1476,21 @@ vdbe_emit_stat_space_clear(struct Parse *parse, const char *stat_table_name,
  * @param constraint_name Name of FK constraint to be dropped.
  *        Must be allocated on head by sqlDbMalloc().
  *        It will be freed in VDBE.
- * @param child_id Id of table which constraint belongs to.
+ * @param child_def Def of table which constraint belongs to.
  */
 static void
 vdbe_emit_fk_constraint_drop(struct Parse *parse_context, char *constraint_name,
-		    uint32_t child_id)
+			     struct space_def *child_def)
 {
 	struct Vdbe *vdbe = sqlGetVdbe(parse_context);
 	assert(vdbe != NULL);
 	int key_reg = sqlGetTempRange(parse_context, 3);
 	sqlVdbeAddOp4(vdbe, OP_String8, 0, key_reg, 0, constraint_name,
 			  P4_DYNAMIC);
-	sqlVdbeAddOp2(vdbe, OP_Integer, child_id,  key_reg + 1);
+	sqlVdbeAddOp2(vdbe, OP_Integer, child_def->id, key_reg + 1);
 	const char *error_msg =
 		tt_sprintf(tnt_errcode_desc(ER_NO_SUCH_CONSTRAINT),
-			   constraint_name);
+			   constraint_name, child_def->name);
 	if (vdbe_emit_halt_with_presence_test(parse_context,
 					      BOX_FK_CONSTRAINT_ID, 0,
 					      key_reg, 2, ER_NO_SUCH_CONSTRAINT,
@@ -1510,21 +1510,22 @@ vdbe_emit_fk_constraint_drop(struct Parse *parse_context, char *constraint_name,
  *
  * @param parser Parsing context.
  * @param ck_name Name of CK constraint to be dropped.
- * @param space_id Id of table which constraint belongs to.
+ * @param space_def Def of table which constraint belongs to.
  */
 static void
 vdbe_emit_ck_constraint_drop(struct Parse *parser, const char *ck_name,
-			     uint32_t space_id)
+			     struct space_def *space_def)
 {
 	struct Vdbe *v = sqlGetVdbe(parser);
 	struct sql *db = v->db;
 	assert(v != NULL);
 	int key_reg = sqlGetTempRange(parser, 3);
-	sqlVdbeAddOp2(v, OP_Integer, space_id,  key_reg);
+	sqlVdbeAddOp2(v, OP_Integer, space_def->id, key_reg);
 	sqlVdbeAddOp4(v, OP_String8, 0, key_reg + 1, 0,
 		      sqlDbStrDup(db, ck_name), P4_DYNAMIC);
 	const char *error_msg =
-		tt_sprintf(tnt_errcode_desc(ER_NO_SUCH_CONSTRAINT), ck_name);
+		tt_sprintf(tnt_errcode_desc(ER_NO_SUCH_CONSTRAINT), ck_name,
+			   space_def->name);
 	if (vdbe_emit_halt_with_presence_test(parser, BOX_CK_CONSTRAINT_ID, 0,
 					      key_reg, 2, ER_NO_SUCH_CONSTRAINT,
 					      error_msg, false, OP_Found) != 0)
@@ -1658,14 +1659,15 @@ sql_code_drop_table(struct Parse *parse_context, struct space *space,
 		char *fk_name_dup = sqlDbStrDup(v->db, child_fk->def->name);
 		if (fk_name_dup == NULL)
 			return;
-		vdbe_emit_fk_constraint_drop(parse_context, fk_name_dup, space_id);
+		vdbe_emit_fk_constraint_drop(parse_context, fk_name_dup,
+					     space->def);
 	}
 	/* Delete all CK constraints. */
 	struct ck_constraint *ck_constraint;
 	rlist_foreach_entry(ck_constraint, &space->ck_constraint, link) {
 		vdbe_emit_ck_constraint_drop(parse_context,
 					     ck_constraint->def->name,
-					     space_id);
+					     space->def);
 	}
 	/*
 	 * Drop all _space and _index entries that refer to the
@@ -2071,7 +2073,7 @@ sql_drop_foreign_key(struct Parse *parse_context)
 		return;
 	}
 	vdbe_emit_fk_constraint_drop(parse_context, constraint_name,
-				     child->def->id);
+				     child->def);
 	/*
 	 * We account changes to row count only if drop of
 	 * foreign keys take place in a separate
diff --git a/test/sql-tap/alter2.test.lua b/test/sql-tap/alter2.test.lua
index 3e21a5f40..759acc9c3 100755
--- a/test/sql-tap/alter2.test.lua
+++ b/test/sql-tap/alter2.test.lua
@@ -256,7 +256,7 @@ test:do_catchsql_test(
         ALTER TABLE child DROP CONSTRAINT fake;
     ]], {
         -- <alter2-5.2>
-        1, "Constraint FAKE does not exist"
+        1, "Constraint 'FAKE' does not exist in space 'CHILD'"
         -- </alter2-5.2>
     })
 
diff --git a/test/sql/checks.result b/test/sql/checks.result
index 4ae0b4c10..7b18e5d6b 100644
--- a/test/sql/checks.result
+++ b/test/sql/checks.result
@@ -801,7 +801,7 @@ box.execute('ALTER TABLE test ADD CONSTRAINT \"some_ck\" CHECK(a < 10);')
 box.execute("ALTER TABLE test DISABLE CHECK CONSTRAINT \"falsch\"")
 ---
 - null
-- Constraint falsch does not exist
+- Constraint 'falsch' does not exist in space 'TEST'
 ...
 box.execute("ALTER TABLE test DISABLE CHECK CONSTRAINT \"some_ck\"")
 ---
-- 
2.21.0 (Apple Git-122)

[Tarantool-patches] [PATCH v2 2/3] sql: don't select from _index during parsing

[Roman Khabibov]

Remove function box_index_by_name() from parser to avoid selects
during parsing. Add the ability to choose index during VDBE code
compilation which will be used to find the tuple to drop from a
system space.

Needed for #4120
---
 src/box/space.h      | 15 +++++++++++
 src/box/sql/build.c  | 60 +++++++++++++++++++++++++++-----------------
 src/box/sql/pragma.c |  8 ++----
 src/box/sql/vdbe.c   | 10 +++++---
 4 files changed, 60 insertions(+), 33 deletions(-)

diff --git a/src/box/space.h b/src/box/space.h
index 9aea4e5be..28885d037 100644
--- a/src/box/space.h
+++ b/src/box/space.h
@@ -287,6 +287,21 @@ space_index(struct space *space, uint32_t id)
 	return NULL;
 }
 
+/**
+ * Get index by index name.
+ * @return NULL if the index is not found.
+ */
+static inline struct index *
+space_index_by_name(struct space *space, const char *index_name)
+{
+	for(uint32_t i = 0; i < space->index_count; i++) {
+		struct index *index = space->index[i];
+		if (strcmp(index_name, index->def->name) == 0)
+			return index;
+	}
+	return NULL;
+}
+
 /**
  * Return true if the unique constraint must be checked for
  * the index with the given id before inserting a tuple into
diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index d9bf8de91..00877b7d8 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -47,7 +47,6 @@
 #include "sqlInt.h"
 #include "vdbeInt.h"
 #include "tarantoolInt.h"
-#include "box/box.h"
 #include "box/ck_constraint.h"
 #include "box/fk_constraint.h"
 #include "box/sequence.h"
@@ -1469,6 +1468,41 @@ vdbe_emit_stat_space_clear(struct Parse *parse, const char *stat_table_name,
 	sql_table_delete_from(parse, src_list, where);
 }
 
+/**
+ * Generate VDBE program to remove entry from _index space.
+ *
+ * @param parse_context Parsing context.
+ * @param name Index name.
+ *        It will be freed in VDBE.
+ * @param space_def Def of table which index belongs to.
+ * @param errcode Type of printing error: "no such index" or
+		  "no such constraint".
+ * @param if_exist True if there was <IF EXISTS> in the query.
+ */
+static void
+vdbe_emit_index_drop(struct Parse *parse_context, const char *name,
+		     struct space_def *space_def, int errcode, bool if_exist)
+{
+	assert(errcode == ER_NO_SUCH_INDEX_NAME ||
+	       errcode == ER_NO_SUCH_CONSTRAINT);
+	struct Vdbe *vdbe = sqlGetVdbe(parse_context);
+	assert(vdbe != NULL);
+	assert(parse_context->db != NULL);
+	int key_reg = sqlGetTempRange(parse_context, 3);
+	sqlVdbeAddOp2(vdbe, OP_Integer, space_def->id, key_reg);
+	sqlVdbeAddOp4(vdbe, OP_String8, 0, key_reg + 1, 0,
+		      sqlDbStrDup(parse_context->db, name), P4_DYNAMIC);
+	const char *error_msg =
+		tt_sprintf(tnt_errcode_desc(errcode), name, space_def->name);
+	if (vdbe_emit_halt_with_presence_test(parse_context, BOX_INDEX_ID, 2,
+					      key_reg, 2, errcode, error_msg,
+					      if_exist, OP_Found) != 0)
+		return;
+	sqlVdbeAddOp3(vdbe, OP_MakeRecord, key_reg, 2, key_reg + 2);
+	sqlVdbeAddOp3(vdbe, OP_SDelete, BOX_INDEX_ID, key_reg + 2, 2);
+	sqlReleaseTempRange(parse_context, key_reg, 3);
+}
+
 /**
  * Generate VDBE program to remove entry from _fk_constraint space.
  *
@@ -2695,29 +2729,9 @@ sql_drop_index(struct Parse *parse_context)
 		parse_context->is_aborted = true;
 		goto exit_drop_index;
 	}
-	uint32_t index_id = box_index_id_by_name(space->def->id, index_name,
-						 strlen(index_name));
-	if (index_id == BOX_ID_NIL) {
-		if (!if_exists) {
-			diag_set(ClientError, ER_NO_SUCH_INDEX_NAME,
-				 index_name, table_name);
-			parse_context->is_aborted = true;
-		}
-		goto exit_drop_index;
-	}
 
-	/*
-	 * Generate code to remove entry from _index space
-	 * But firstly, delete statistics since schema
-	 * changes after DDL.
-	 */
-	int record_reg = ++parse_context->nMem;
-	int space_id_reg = ++parse_context->nMem;
-	int index_id_reg = ++parse_context->nMem;
-	sqlVdbeAddOp2(v, OP_Integer, space->def->id, space_id_reg);
-	sqlVdbeAddOp2(v, OP_Integer, index_id, index_id_reg);
-	sqlVdbeAddOp3(v, OP_MakeRecord, space_id_reg, 2, record_reg);
-	sqlVdbeAddOp2(v, OP_SDelete, BOX_INDEX_ID, record_reg);
+	vdbe_emit_index_drop(parse_context, index_name, space->def,
+			     ER_NO_SUCH_INDEX_NAME, if_exists);
 	sqlVdbeChangeP5(v, OPFLAG_NCHANGE);
  exit_drop_index:
 	sqlSrcListDelete(db, table_list);
diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
index a77bf4b16..c15f2e0d1 100644
--- a/src/box/sql/pragma.c
+++ b/src/box/sql/pragma.c
@@ -33,7 +33,6 @@
  * This file contains code used to implement the PRAGMA command.
  */
 #include "box/index.h"
-#include "box/box.h"
 #include "box/tuple.h"
 #include "box/fk_constraint.h"
 #include "box/schema.h"
@@ -192,12 +191,9 @@ sql_pragma_index_info(struct Parse *parse,
 	struct space *space = space_by_name(tbl_name);
 	if (space == NULL)
 		return;
-	uint32_t iid = box_index_id_by_name(space->def->id, idx_name,
-					    strlen(idx_name));
-	if (iid == BOX_ID_NIL)
+	struct index *idx = space_index_by_name(space, idx_name);
+	if (idx == NULL)
 		return;
-	struct index *idx = space_index(space, iid);
-	assert(idx != NULL);
 	parse->nMem = 6;
 	struct Vdbe *v = sqlGetVdbe(parse);
 	assert(v != NULL);
diff --git a/src/box/sql/vdbe.c b/src/box/sql/vdbe.c
index 620d74e66..912a10153 100644
--- a/src/box/sql/vdbe.c
+++ b/src/box/sql/vdbe.c
@@ -4460,11 +4460,12 @@ case OP_SInsert: {
 	break;
 }
 
-/* Opcode: SDelete P1 P2 * * P5
- * Synopsis: space id = P1, key = r[P2]
+/* Opcode: SDelete P1 P2 P3 * P5
+ * Synopsis: space id = P1, key = r[P2], searching index id = P3
  *
  * This opcode is used only during DDL routine.
- * Delete entry with given key from system space.
+ * Delete entry with given key from system space. P3 is the index
+ * number by which to search for the key.
  *
  * If P5 is set to OPFLAG_NCHANGE, account overall changes
  * made to database.
@@ -4472,13 +4473,14 @@ case OP_SInsert: {
 case OP_SDelete: {
 	assert(pOp->p1 > 0);
 	assert(pOp->p2 >= 0);
+	assert(pOp->p3 >= 0);
 
 	pIn2 = &aMem[pOp->p2];
 	struct space *space = space_by_id(pOp->p1);
 	assert(space != NULL);
 	assert(space_is_system(space));
 	assert(p->errorAction == ON_CONFLICT_ACTION_ABORT);
-	if (sql_delete_by_key(space, 0, pIn2->z, pIn2->n) != 0)
+	if (sql_delete_by_key(space, pOp->p3, pIn2->z, pIn2->n) != 0)
 		goto abort_due_to_error;
 	if (pOp->p5 & OPFLAG_NCHANGE)
 		p->nChange++;
-- 
2.21.0 (Apple Git-122)

Re: [Tarantool-patches] [PATCH v2 2/3] sql: don't select from _index during parsing

[Vladislav Shpilevoy]

Thanks for the patch!

See 2 comments below.

> diff --git a/src/box/sql/build.c b/src/box/sql/build.c
> index d9bf8de91..00877b7d8 100644
> --- a/src/box/sql/build.c
> +++ b/src/box/sql/build.c
> @@ -47,7 +47,6 @@
>  #include "sqlInt.h"
>  #include "vdbeInt.h"
>  #include "tarantoolInt.h"
> -#include "box/box.h"
>  #include "box/ck_constraint.h"
>  #include "box/fk_constraint.h"
>  #include "box/sequence.h"
> @@ -1469,6 +1468,41 @@ vdbe_emit_stat_space_clear(struct Parse *parse, const char *stat_table_name,
>  	sql_table_delete_from(parse, src_list, where);
>  }
>  
> +/**
> + * Generate VDBE program to remove entry from _index space.
> + *
> + * @param parse_context Parsing context.
> + * @param name Index name.
> + *        It will be freed in VDBE.

1. This easily fits into one line. Also I don't understand what does
it mean 'freed in VDBE'. From what I see, this function has nothing
to do with freeing 'name' argument, as well as VDBE. It is freed
by the caller in the end of sql_drop_index().

> + * @param space_def Def of table which index belongs to.
> + * @param errcode Type of printing error: "no such index" or
> +		  "no such constraint".
> + * @param if_exist True if there was <IF EXISTS> in the query.
> + */
> +static void
> +vdbe_emit_index_drop(struct Parse *parse_context, const char *name,
> +		     struct space_def *space_def, int errcode, bool if_exist)
> +{
> +	assert(errcode == ER_NO_SUCH_INDEX_NAME ||
> +	       errcode == ER_NO_SUCH_CONSTRAINT);
> +	struct Vdbe *vdbe = sqlGetVdbe(parse_context);
> +	assert(vdbe != NULL);
> +	assert(parse_context->db != NULL);
> +	int key_reg = sqlGetTempRange(parse_context, 3);
> +	sqlVdbeAddOp2(vdbe, OP_Integer, space_def->id, key_reg);
> +	sqlVdbeAddOp4(vdbe, OP_String8, 0, key_reg + 1, 0,
> +		      sqlDbStrDup(parse_context->db, name), P4_DYNAMIC);
> +	const char *error_msg =
> +		tt_sprintf(tnt_errcode_desc(errcode), name, space_def->name);
> +	if (vdbe_emit_halt_with_presence_test(parse_context, BOX_INDEX_ID, 2,
> +					      key_reg, 2, errcode, error_msg,
> +					      if_exist, OP_Found) != 0)
> +		return;
> +	sqlVdbeAddOp3(vdbe, OP_MakeRecord, key_reg, 2, key_reg + 2);
> +	sqlVdbeAddOp3(vdbe, OP_SDelete, BOX_INDEX_ID, key_reg + 2, 2);
> +	sqlReleaseTempRange(parse_context, key_reg, 3);
> +}
> diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
> index a77bf4b16..c15f2e0d1 100644
> --- a/src/box/sql/pragma.c
> +++ b/src/box/sql/pragma.c
> @@ -192,12 +191,9 @@ sql_pragma_index_info(struct Parse *parse,
>  	struct space *space = space_by_name(tbl_name);
>  	if (space == NULL)
>  		return;
> -	uint32_t iid = box_index_id_by_name(space->def->id, idx_name,
> -					    strlen(idx_name));
> -	if (iid == BOX_ID_NIL)
> +	struct index *idx = space_index_by_name(space, idx_name);
> +	if (idx == NULL)
>  		return;
> -	struct index *idx = space_index(space, iid);
> -	assert(idx != NULL);

2. Yeah, ok, good enough. The final goal should be to stop using
even struct space pointer here. Sometime later.

>  	parse->nMem = 6;
>  	struct Vdbe *v = sqlGetVdbe(parse);
>  	assert(v != NULL);

Re: [Tarantool-patches] [PATCH v2 0/3] Add ability to drop constraints

[Vladislav Shpilevoy]

Hi! Thanks for the patchset!

Almost ready to push, good patch. I have very
few nits.

On 29/02/2020 13:46, Roman Khabibov wrote:
> @ChangeLog
> - Add function space_index_by_name().
> - Add ability to spacify searching index in OP_SDelete.
> - Add function vdbe_emit_index_drop() to drop index by name.
> - Remove box_index_by_name() from build.c and pragma.c.
> - Rewrite function sql_drop_foreign_key() to  sql_drop_constraint().
> - Add ability to drop all the types of constraints.
> - Modify "no such constrait" error message.

Sorry, this is not a change log which is needed for the
release notes. See examples in
https://github.com/tarantool/tarantool/releases.

Users don't care about internal functions being moved/deleted/
renamed/patched. Also I don't see a word about DROP CONSTRAINT,
which was this ticket about in the first place.

Also I see that you somewhy split the thread in two parts, so
I received only 0/3, 1/3 and 2/3 letters in this thread, while
3/3 was sent in response to the old thread - please, don't do
that. It complicates review process. In an old thread you should
send only answers on comments. All new patches should go in a new
thread, if you decided to start it.

Last thing - the branch is very outdated. Please, rebase it on
the latest master.

> Hello, everybody!
> As Nikita requested, I performed the patch to remove
> box_index_by_name() from build.c and pragma.c, but what about
> analyze.c? Still had to add space_index_by_name() to use in
> pragma.c, beacuse struct index is required.

We can't do anything about analyze, because it is disabled.

> Roman Khabibov (3):
>   sql: improve "no such constraint" error message
>   sql: don't select from _index during parsing
>   sql: support constraint drop
> 
>  src/box/constraint_id.h      |   1 +
>  src/box/errcode.h            |   2 +-
>  src/box/space.h              |  15 ++++
>  src/box/sql/alter.c          |   2 +-
>  src/box/sql/build.c          | 143 ++++++++++++++++++++++-------------
>  src/box/sql/parse.y          |   4 +-
>  src/box/sql/parse_def.h      |  11 +--
>  src/box/sql/pragma.c         |   8 +-
>  src/box/sql/sqlInt.h         |   7 +-
>  src/box/sql/vdbe.c           |  10 ++-
>  test/sql-tap/alter2.test.lua |   2 +-
>  test/sql/checks.result       |   2 +-
>  test/sql/constraint.result   |  81 ++++++++++++++++++++
>  test/sql/constraint.test.lua |  28 +++++++
>  14 files changed, 240 insertions(+), 76 deletions(-)
> 

Re: [Tarantool-patches] [PATCH v2 1/3] sql: improve "no such constraint" error message

[Vladislav Shpilevoy]

On 29/02/2020 13:46, Roman Khabibov wrote:
> Clarify the error message for better user handling. Add the name
> of space where the constraint under dropping didn't founded.

didn't -> wasn't

Re: [Tarantool-patches] [PATCH v2 0/3] Add ability to drop constraints

[Nikita Pettik]

On 29 Feb 15:46, Roman Khabibov wrote:
> @ChangeLog
> - Add function space_index_by_name().
> - Add ability to spacify searching index in OP_SDelete.
> - Add function vdbe_emit_index_drop() to drop index by name.
> - Remove box_index_by_name() from build.c and pragma.c.
> - Rewrite function sql_drop_foreign_key() to  sql_drop_constraint().
> - Add ability to drop all the types of constraints.
> - Modify "no such constrait" error message.
> 
> Hello, everybody!
> As Nikita requested, I performed the patch to remove
> box_index_by_name() from build.c and pragma.c, but what about
> analyze.c? Still had to add space_index_by_name() to use in
> pragma.c, beacuse struct index is required.

analyze.c now is unreachable. Even if you fix those usages, you won't
be able to test them.

> Roman Khabibov (3):
>   sql: improve "no such constraint" error message
>   sql: don't select from _index during parsing
>   sql: support constraint drop
> 
>  src/box/constraint_id.h      |   1 +
>  src/box/errcode.h            |   2 +-
>  src/box/space.h              |  15 ++++
>  src/box/sql/alter.c          |   2 +-
>  src/box/sql/build.c          | 143 ++++++++++++++++++++++-------------
>  src/box/sql/parse.y          |   4 +-
>  src/box/sql/parse_def.h      |  11 +--
>  src/box/sql/pragma.c         |   8 +-
>  src/box/sql/sqlInt.h         |   7 +-
>  src/box/sql/vdbe.c           |  10 ++-
>  test/sql-tap/alter2.test.lua |   2 +-
>  test/sql/checks.result       |   2 +-
>  test/sql/constraint.result   |  81 ++++++++++++++++++++
>  test/sql/constraint.test.lua |  28 +++++++
>  14 files changed, 240 insertions(+), 76 deletions(-)
> 
> -- 
> 2.21.0 (Apple Git-122)
> 

Re: [Tarantool-patches] [PATCH v2 2/3] sql: don't select from _index during parsing

[Roman Khabibov]

> On Feb 29, 2020, at 18:31, Vladislav Shpilevoy <v.shpilevoy@tarantool.org> wrote:
> 
> Thanks for the patch!
> 
> See 2 comments below.
> 
>> diff --git a/src/box/sql/build.c b/src/box/sql/build.c
>> index d9bf8de91..00877b7d8 100644
>> --- a/src/box/sql/build.c
>> +++ b/src/box/sql/build.c
>> @@ -47,7 +47,6 @@
>> #include "sqlInt.h"
>> #include "vdbeInt.h"
>> #include "tarantoolInt.h"
>> -#include "box/box.h"
>> #include "box/ck_constraint.h"
>> #include "box/fk_constraint.h"
>> #include "box/sequence.h"
>> @@ -1469,6 +1468,41 @@ vdbe_emit_stat_space_clear(struct Parse *parse, const char *stat_table_name,
>> 	sql_table_delete_from(parse, src_list, where);
>> }
>> 
>> +/**
>> + * Generate VDBE program to remove entry from _index space.
>> + *
>> + * @param parse_context Parsing context.
>> + * @param name Index name.
>> + *        It will be freed in VDBE.
> 
> 1. This easily fits into one line. Also I don't understand what does
> it mean 'freed in VDBE'. From what I see, this function has nothing
> to do with freeing 'name' argument, as well as VDBE. It is freed
> by the caller in the end of sql_drop_index().
Oops. This line turned out to be a case here.

>> + * @param space_def Def of table which index belongs to.
>> + * @param errcode Type of printing error: "no such index" or
>> +		  "no such constraint".
>> + * @param if_exist True if there was <IF EXISTS> in the query.
>> + */
>> +static void
>> +vdbe_emit_index_drop(struct Parse *parse_context, const char *name,
>> +		     struct space_def *space_def, int errcode, bool if_exist)
>> +{
>> +	assert(errcode == ER_NO_SUCH_INDEX_NAME ||
>> +	       errcode == ER_NO_SUCH_CONSTRAINT);
>> +	struct Vdbe *vdbe = sqlGetVdbe(parse_context);
>> +	assert(vdbe != NULL);
>> +	assert(parse_context->db != NULL);
>> +	int key_reg = sqlGetTempRange(parse_context, 3);
>> +	sqlVdbeAddOp2(vdbe, OP_Integer, space_def->id, key_reg);
>> +	sqlVdbeAddOp4(vdbe, OP_String8, 0, key_reg + 1, 0,
>> +		      sqlDbStrDup(parse_context->db, name), P4_DYNAMIC);
>> +	const char *error_msg =
>> +		tt_sprintf(tnt_errcode_desc(errcode), name, space_def->name);
>> +	if (vdbe_emit_halt_with_presence_test(parse_context, BOX_INDEX_ID, 2,
>> +					      key_reg, 2, errcode, error_msg,
>> +					      if_exist, OP_Found) != 0)
>> +		return;
>> +	sqlVdbeAddOp3(vdbe, OP_MakeRecord, key_reg, 2, key_reg + 2);
>> +	sqlVdbeAddOp3(vdbe, OP_SDelete, BOX_INDEX_ID, key_reg + 2, 2);
>> +	sqlReleaseTempRange(parse_context, key_reg, 3);
>> +}
>> diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
>> index a77bf4b16..c15f2e0d1 100644
>> --- a/src/box/sql/pragma.c
>> +++ b/src/box/sql/pragma.c
>> @@ -192,12 +191,9 @@ sql_pragma_index_info(struct Parse *parse,
>> 	struct space *space = space_by_name(tbl_name);
>> 	if (space == NULL)
>> 		return;
>> -	uint32_t iid = box_index_id_by_name(space->def->id, idx_name,
>> -					    strlen(idx_name));
>> -	if (iid == BOX_ID_NIL)
>> +	struct index *idx = space_index_by_name(space, idx_name);
>> +	if (idx == NULL)
>> 		return;
>> -	struct index *idx = space_index(space, iid);
>> -	assert(idx != NULL);
> 
> 2. Yeah, ok, good enough. The final goal should be to stop using
> even struct space pointer here. Sometime later.
> 
>> 	parse->nMem = 6;
>> 	struct Vdbe *v = sqlGetVdbe(parse);
>> 	assert(v != NULL);

Re: [Tarantool-patches] [PATCH v2 1/3] sql: improve "no such constraint" error message

[Roman Khabibov]

> On Feb 29, 2020, at 18:31, Vladislav Shpilevoy <v.shpilevoy@tarantool.org> wrote:
> 
> 
> 
> On 29/02/2020 13:46, Roman Khabibov wrote:
>> Clarify the error message for better user handling. Add the name
>> of space where the constraint under dropping didn't founded.
> 
> didn't -> wasn’t
Fixed.

Re: [Tarantool-patches] [PATCH v2 2/3] sql: don't select from _index during parsing

[Roman Khabibov]

Don’t see the previous mail of this commit.


sql: don't select from _index during parsing

Remove function box_index_by_name() from parser to avoid selects
during parsing. Add the ability to choose index during VDBE code
compilation which will be used to find the tuple to drop from a
system space.

Needed for #4120
---
 src/box/space.h      | 19 +++++++++++
 src/box/sql/build.c  | 79 +++++++++++++++++++++-----------------------
 src/box/sql/pragma.c |  8 ++---
 src/box/sql/vdbe.c   | 10 +++---
 4 files changed, 64 insertions(+), 52 deletions(-)

diff --git a/src/box/space.h b/src/box/space.h
index 9aea4e5be..bbdd3ef70 100644
--- a/src/box/space.h
+++ b/src/box/space.h
@@ -287,6 +287,25 @@ space_index(struct space *space, uint32_t id)
 	return NULL;
 }
 
+/**
+ * Get index by index name.
+ *
+ * @param space Space index belongs to.
+ * @param index_name Name of index to be found.
+ *
+ * @retval NULL if the index is not found.
+ */
+static inline struct index *
+space_index_by_name(struct space *space, const char *index_name)
+{
+	for(uint32_t i = 0; i < space->index_count; i++) {
+		struct index *index = space->index[i];
+		if (strcmp(index_name, index->def->name) == 0)
+			return index;
+	}
+	return NULL;
+}
+
 /**
  * Return true if the unique constraint must be checked for
  * the index with the given id before inserting a tuple into
diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index d9bf8de91..fef069640 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -47,7 +47,6 @@
 #include "sqlInt.h"
 #include "vdbeInt.h"
 #include "tarantoolInt.h"
-#include "box/box.h"
 #include "box/ck_constraint.h"
 #include "box/fk_constraint.h"
 #include "box/sequence.h"
@@ -116,24 +115,6 @@ sql_finish_coding(struct Parse *parse_context)
 		parse_context->is_aborted = true;
 	}
 }
-/**
- * Find index by its name.
- *
- * @param space Space index belongs to.
- * @param name Name of index to be found.
- *
- * @retval NULL in case index doesn't exist.
- */
-static struct index *
-sql_space_index_by_name(struct space *space, const char *name)
-{
-	for (uint32_t i = 0; i < space->index_count; ++i) {
-		struct index *idx = space->index[i];
-		if (strcmp(name, idx->def->name) == 0)
-			return idx;
-	}
-	return NULL;
-}
 
 bool
 sql_space_column_is_in_pk(struct space *space, uint32_t column)
@@ -1469,6 +1450,40 @@ vdbe_emit_stat_space_clear(struct Parse *parse, const char *stat_table_name,
 	sql_table_delete_from(parse, src_list, where);
 }
 
+/**
+ * Generate VDBE program to remove entry from _index space.
+ *
+ * @param parse_context Parsing context.
+ * @param name Index name.
+ * @param space_def Def of table which index belongs to.
+ * @param errcode Type of printing error: "no such index" or
+ *                "no such constraint".
+ * @param if_exist True if there was <IF EXISTS> in the query.
+ */
+static void
+vdbe_emit_index_drop(struct Parse *parse_context, const char *name,
+		     struct space_def *space_def, int errcode, bool if_exist)
+{
+	assert(errcode == ER_NO_SUCH_INDEX_NAME ||
+	       errcode == ER_NO_SUCH_CONSTRAINT);
+	struct Vdbe *vdbe = sqlGetVdbe(parse_context);
+	assert(vdbe != NULL);
+	assert(parse_context->db != NULL);
+	int key_reg = sqlGetTempRange(parse_context, 3);
+	sqlVdbeAddOp2(vdbe, OP_Integer, space_def->id, key_reg);
+	sqlVdbeAddOp4(vdbe, OP_String8, 0, key_reg + 1, 0,
+		      sqlDbStrDup(parse_context->db, name), P4_DYNAMIC);
+	const char *error_msg =
+		tt_sprintf(tnt_errcode_desc(errcode), name, space_def->name);
+	if (vdbe_emit_halt_with_presence_test(parse_context, BOX_INDEX_ID, 2,
+					      key_reg, 2, errcode, error_msg,
+					      if_exist, OP_Found) != 0)
+		return;
+	sqlVdbeAddOp3(vdbe, OP_MakeRecord, key_reg, 2, key_reg + 2);
+	sqlVdbeAddOp3(vdbe, OP_SDelete, BOX_INDEX_ID, key_reg + 2, 2);
+	sqlReleaseTempRange(parse_context, key_reg, 3);
+}
+
 /**
  * Generate VDBE program to remove entry from _fk_constraint space.
  *
@@ -2401,7 +2416,7 @@ sql_create_index(struct Parse *parse) {
 			parse->is_aborted = true;
 			goto exit_create_index;
 		}
-		if (sql_space_index_by_name(space, name) != NULL) {
+		if (space_index_by_name(space, name) != NULL) {
 			if (! create_entity_def->if_not_exist) {
 				diag_set(ClientError, ER_INDEX_EXISTS_IN_SPACE,
 					 name, def->name);
@@ -2695,29 +2710,9 @@ sql_drop_index(struct Parse *parse_context)
 		parse_context->is_aborted = true;
 		goto exit_drop_index;
 	}
-	uint32_t index_id = box_index_id_by_name(space->def->id, index_name,
-						 strlen(index_name));
-	if (index_id == BOX_ID_NIL) {
-		if (!if_exists) {
-			diag_set(ClientError, ER_NO_SUCH_INDEX_NAME,
-				 index_name, table_name);
-			parse_context->is_aborted = true;
-		}
-		goto exit_drop_index;
-	}
 
-	/*
-	 * Generate code to remove entry from _index space
-	 * But firstly, delete statistics since schema
-	 * changes after DDL.
-	 */
-	int record_reg = ++parse_context->nMem;
-	int space_id_reg = ++parse_context->nMem;
-	int index_id_reg = ++parse_context->nMem;
-	sqlVdbeAddOp2(v, OP_Integer, space->def->id, space_id_reg);
-	sqlVdbeAddOp2(v, OP_Integer, index_id, index_id_reg);
-	sqlVdbeAddOp3(v, OP_MakeRecord, space_id_reg, 2, record_reg);
-	sqlVdbeAddOp2(v, OP_SDelete, BOX_INDEX_ID, record_reg);
+	vdbe_emit_index_drop(parse_context, index_name, space->def,
+			     ER_NO_SUCH_INDEX_NAME, if_exists);
 	sqlVdbeChangeP5(v, OPFLAG_NCHANGE);
  exit_drop_index:
 	sqlSrcListDelete(db, table_list);
diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
index a77bf4b16..c15f2e0d1 100644
--- a/src/box/sql/pragma.c
+++ b/src/box/sql/pragma.c
@@ -33,7 +33,6 @@
  * This file contains code used to implement the PRAGMA command.
  */
 #include "box/index.h"
-#include "box/box.h"
 #include "box/tuple.h"
 #include "box/fk_constraint.h"
 #include "box/schema.h"
@@ -192,12 +191,9 @@ sql_pragma_index_info(struct Parse *parse,
 	struct space *space = space_by_name(tbl_name);
 	if (space == NULL)
 		return;
-	uint32_t iid = box_index_id_by_name(space->def->id, idx_name,
-					    strlen(idx_name));
-	if (iid == BOX_ID_NIL)
+	struct index *idx = space_index_by_name(space, idx_name);
+	if (idx == NULL)
 		return;
-	struct index *idx = space_index(space, iid);
-	assert(idx != NULL);
 	parse->nMem = 6;
 	struct Vdbe *v = sqlGetVdbe(parse);
 	assert(v != NULL);
diff --git a/src/box/sql/vdbe.c b/src/box/sql/vdbe.c
index 620d74e66..912a10153 100644
--- a/src/box/sql/vdbe.c
+++ b/src/box/sql/vdbe.c
@@ -4460,11 +4460,12 @@ case OP_SInsert: {
 	break;
 }
 
-/* Opcode: SDelete P1 P2 * * P5
- * Synopsis: space id = P1, key = r[P2]
+/* Opcode: SDelete P1 P2 P3 * P5
+ * Synopsis: space id = P1, key = r[P2], searching index id = P3
  *
  * This opcode is used only during DDL routine.
- * Delete entry with given key from system space.
+ * Delete entry with given key from system space. P3 is the index
+ * number by which to search for the key.
  *
  * If P5 is set to OPFLAG_NCHANGE, account overall changes
  * made to database.
@@ -4472,13 +4473,14 @@ case OP_SInsert: {
 case OP_SDelete: {
 	assert(pOp->p1 > 0);
 	assert(pOp->p2 >= 0);
+	assert(pOp->p3 >= 0);
 
 	pIn2 = &aMem[pOp->p2];
 	struct space *space = space_by_id(pOp->p1);
 	assert(space != NULL);
 	assert(space_is_system(space));
 	assert(p->errorAction == ON_CONFLICT_ACTION_ABORT);
-	if (sql_delete_by_key(space, 0, pIn2->z, pIn2->n) != 0)
+	if (sql_delete_by_key(space, pOp->p3, pIn2->z, pIn2->n) != 0)
 		goto abort_due_to_error;
 	if (pOp->p5 & OPFLAG_NCHANGE)
 		p->nChange++;
-- 
2.21.0 (Apple Git-122)

[Tarantool-patches] [PATCH v2 2/3] sql: don't select from _index during parsing

[Roman Khabibov]

Remove function box_index_by_name() from parser to avoid selects
during parsing. Add the ability to choose index during VDBE code
compilation which will be used to find the tuple to drop from a
system space.

Needed for #4120
---
 src/box/space.h      | 15 +++++++++++
 src/box/sql/build.c  | 59 +++++++++++++++++++++++++++-----------------
 src/box/sql/pragma.c |  8 ++----
 src/box/sql/vdbe.c   | 10 +++++---
 4 files changed, 59 insertions(+), 33 deletions(-)

diff --git a/src/box/space.h b/src/box/space.h
index 9aea4e5be..28885d037 100644
--- a/src/box/space.h
+++ b/src/box/space.h
@@ -287,6 +287,21 @@ space_index(struct space *space, uint32_t id)
 	return NULL;
 }
 
+/**
+ * Get index by index name.
+ * @return NULL if the index is not found.
+ */
+static inline struct index *
+space_index_by_name(struct space *space, const char *index_name)
+{
+	for(uint32_t i = 0; i < space->index_count; i++) {
+		struct index *index = space->index[i];
+		if (strcmp(index_name, index->def->name) == 0)
+			return index;
+	}
+	return NULL;
+}
+
 /**
  * Return true if the unique constraint must be checked for
  * the index with the given id before inserting a tuple into
diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index d9bf8de91..e0f690fc2 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -47,7 +47,6 @@
 #include "sqlInt.h"
 #include "vdbeInt.h"
 #include "tarantoolInt.h"
-#include "box/box.h"
 #include "box/ck_constraint.h"
 #include "box/fk_constraint.h"
 #include "box/sequence.h"
@@ -1469,6 +1468,40 @@ vdbe_emit_stat_space_clear(struct Parse *parse, const char *stat_table_name,
 	sql_table_delete_from(parse, src_list, where);
 }
 
+/**
+ * Generate VDBE program to remove entry from _index space.
+ *
+ * @param parse_context Parsing context.
+ * @param name Index name.
+ * @param space_def Def of table which index belongs to.
+ * @param errcode Type of printing error: "no such index" or
+ *                "no such constraint".
+ * @param if_exist True if there was <IF EXISTS> in the query.
+ */
+static void
+vdbe_emit_index_drop(struct Parse *parse_context, const char *name,
+		     struct space_def *space_def, int errcode, bool if_exist)
+{
+	assert(errcode == ER_NO_SUCH_INDEX_NAME ||
+	       errcode == ER_NO_SUCH_CONSTRAINT);
+	struct Vdbe *vdbe = sqlGetVdbe(parse_context);
+	assert(vdbe != NULL);
+	assert(parse_context->db != NULL);
+	int key_reg = sqlGetTempRange(parse_context, 3);
+	sqlVdbeAddOp2(vdbe, OP_Integer, space_def->id, key_reg);
+	sqlVdbeAddOp4(vdbe, OP_String8, 0, key_reg + 1, 0,
+		      sqlDbStrDup(parse_context->db, name), P4_DYNAMIC);
+	const char *error_msg =
+		tt_sprintf(tnt_errcode_desc(errcode), name, space_def->name);
+	if (vdbe_emit_halt_with_presence_test(parse_context, BOX_INDEX_ID, 2,
+					      key_reg, 2, errcode, error_msg,
+					      if_exist, OP_Found) != 0)
+		return;
+	sqlVdbeAddOp3(vdbe, OP_MakeRecord, key_reg, 2, key_reg + 2);
+	sqlVdbeAddOp3(vdbe, OP_SDelete, BOX_INDEX_ID, key_reg + 2, 2);
+	sqlReleaseTempRange(parse_context, key_reg, 3);
+}
+
 /**
  * Generate VDBE program to remove entry from _fk_constraint space.
  *
@@ -2695,29 +2728,9 @@ sql_drop_index(struct Parse *parse_context)
 		parse_context->is_aborted = true;
 		goto exit_drop_index;
 	}
-	uint32_t index_id = box_index_id_by_name(space->def->id, index_name,
-						 strlen(index_name));
-	if (index_id == BOX_ID_NIL) {
-		if (!if_exists) {
-			diag_set(ClientError, ER_NO_SUCH_INDEX_NAME,
-				 index_name, table_name);
-			parse_context->is_aborted = true;
-		}
-		goto exit_drop_index;
-	}
 
-	/*
-	 * Generate code to remove entry from _index space
-	 * But firstly, delete statistics since schema
-	 * changes after DDL.
-	 */
-	int record_reg = ++parse_context->nMem;
-	int space_id_reg = ++parse_context->nMem;
-	int index_id_reg = ++parse_context->nMem;
-	sqlVdbeAddOp2(v, OP_Integer, space->def->id, space_id_reg);
-	sqlVdbeAddOp2(v, OP_Integer, index_id, index_id_reg);
-	sqlVdbeAddOp3(v, OP_MakeRecord, space_id_reg, 2, record_reg);
-	sqlVdbeAddOp2(v, OP_SDelete, BOX_INDEX_ID, record_reg);
+	vdbe_emit_index_drop(parse_context, index_name, space->def,
+			     ER_NO_SUCH_INDEX_NAME, if_exists);
 	sqlVdbeChangeP5(v, OPFLAG_NCHANGE);
  exit_drop_index:
 	sqlSrcListDelete(db, table_list);
diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
index a77bf4b16..c15f2e0d1 100644
--- a/src/box/sql/pragma.c
+++ b/src/box/sql/pragma.c
@@ -33,7 +33,6 @@
  * This file contains code used to implement the PRAGMA command.
  */
 #include "box/index.h"
-#include "box/box.h"
 #include "box/tuple.h"
 #include "box/fk_constraint.h"
 #include "box/schema.h"
@@ -192,12 +191,9 @@ sql_pragma_index_info(struct Parse *parse,
 	struct space *space = space_by_name(tbl_name);
 	if (space == NULL)
 		return;
-	uint32_t iid = box_index_id_by_name(space->def->id, idx_name,
-					    strlen(idx_name));
-	if (iid == BOX_ID_NIL)
+	struct index *idx = space_index_by_name(space, idx_name);
+	if (idx == NULL)
 		return;
-	struct index *idx = space_index(space, iid);
-	assert(idx != NULL);
 	parse->nMem = 6;
 	struct Vdbe *v = sqlGetVdbe(parse);
 	assert(v != NULL);
diff --git a/src/box/sql/vdbe.c b/src/box/sql/vdbe.c
index 620d74e66..912a10153 100644
--- a/src/box/sql/vdbe.c
+++ b/src/box/sql/vdbe.c
@@ -4460,11 +4460,12 @@ case OP_SInsert: {
 	break;
 }
 
-/* Opcode: SDelete P1 P2 * * P5
- * Synopsis: space id = P1, key = r[P2]
+/* Opcode: SDelete P1 P2 P3 * P5
+ * Synopsis: space id = P1, key = r[P2], searching index id = P3
  *
  * This opcode is used only during DDL routine.
- * Delete entry with given key from system space.
+ * Delete entry with given key from system space. P3 is the index
+ * number by which to search for the key.
  *
  * If P5 is set to OPFLAG_NCHANGE, account overall changes
  * made to database.
@@ -4472,13 +4473,14 @@ case OP_SInsert: {
 case OP_SDelete: {
 	assert(pOp->p1 > 0);
 	assert(pOp->p2 >= 0);
+	assert(pOp->p3 >= 0);
 
 	pIn2 = &aMem[pOp->p2];
 	struct space *space = space_by_id(pOp->p1);
 	assert(space != NULL);
 	assert(space_is_system(space));
 	assert(p->errorAction == ON_CONFLICT_ACTION_ABORT);
-	if (sql_delete_by_key(space, 0, pIn2->z, pIn2->n) != 0)
+	if (sql_delete_by_key(space, pOp->p3, pIn2->z, pIn2->n) != 0)
 		goto abort_due_to_error;
 	if (pOp->p5 & OPFLAG_NCHANGE)
 		p->nChange++;
-- 
2.21.0 (Apple Git-122)