[tarantool-patches] Re: [PATCH 2/2] sql: statistics removal after dropping an index

Hollow111 hollow653 at gmail.com
Wed Apr 4 19:34:31 MSK 2018


ср, 4 апр. 2018 г. в 19:11, n.pettik <korablev at tarantool.org>:

> Now, patch looks way better. Keep fixing minor remarks.
> Also, it is better to push your changes, so that I can check
> Travis status (i.e. make sure that all tests have passed).
>
>
> On 4 Apr 2018, at 18:46, Hollow111 <hollow653 at gmail.com> wrote:
>
>
>
> ср, 4 апр. 2018 г. в 17:06, n.pettik <korablev at tarantool.org>:
>
>> Please, don’t hurry when working on patch.
>> Consider carefully each fix and comment: there is no any deadline.
>>
>> You don’t have to send second patch version.
>> This patch is pretty small, so you can answer to this letter and
>> pin your changes. For example: you won’t change tests (since they are OK),
>> so don’t include them in provided diff.
>>
>> > On 4 Apr 2018, at 00:37, N.Tatunov <hollow653 at gmail.com> wrote:
>> >
>> > Currently dropping an index leads to removal of
>> > all the entries containing the certain index name
>> > in "_sql_statN" tables. Thus far analyze routine was fixed
>> > so it seems that the indexes from the different tables but
>> > with the same names should work more properly.
>> >
>> > Closes: #3264
>> > ---
>> >
>> > Branch:
>> https://github.com/tarantool/tarantool/tree/N_Tatunov/gh-3264-stat-table-entries-removal
>> > Issue: https://github.com/tarantool/tarantool/issues/3264
>> >
>> > src/box/sql/build.c                    |  41 ++++++-----
>> > test/sql/sql-statN-index-drop.result   | 127
>> +++++++++++++++++++++++++++++++++
>> > test/sql/sql-statN-index-drop.test.lua |  54 ++++++++++++++
>> > 3 files changed, 206 insertions(+), 16 deletions(-)
>> > create mode 100644 test/sql/sql-statN-index-drop.result
>> > create mode 100644 test/sql/sql-statN-index-drop.test.lua
>> >
>> > diff --git a/src/box/sql/build.c b/src/box/sql/build.c
>> > index 5e3ed0f..44d7548 100644
>> > --- a/src/box/sql/build.c
>> > +++ b/src/box/sql/build.c
>> > @@ -2207,25 +2207,34 @@ sqliteViewResetAll(sqlite3 * db)
>> > #endif                                /* SQLITE_OMIT_VIEW */
>> >
>> > /*
>> > - * Remove entries from the sqlite_statN tables (for N in (1,2,3))
>> > + * Remove entries from the _sql_statN tables (for N in (1, 4))
>> >  * after a DROP INDEX or DROP TABLE command.
>> >  */
>>
>> Comment prior to function starts from /**.
>> Your provide short description (it is already there),
>> describe arguments and return value with @param and @retval tags.
>> You can find more information by searching ‘doxygen comments’.
>>
>> > static void
>> > -sqlite3ClearStatTables(Parse * pParse,       /* The parsing context */
>> > -                    const char *zType,       /* "idx" or "tbl" */
>> > -                    const char *zName        /* Name of index or table
>> */
>> > +sql_clear_stat_tables(Parse * pParse,        /* The parsing context */
>>
>> pParse and zType are examples of Hungarian notation:
>> you don’t need ‘p’ and ‘z’ prefixes. Moreover, you can remove comment
>> right after arguments, since args will be described above within oxygen
>> comment.
>>
>> > +                    const char *zType,           /* "idx" or "tbl" */
>> > +               const char *table_name,  /* Name of the table*/
>> > +                    const char *idx_name     /* Name of the index*/
>> >     )
>> > {
>> > -     int i;
>> > -     for (i = 1; i <= 4; i++) {
>> > -             char zTab[24];
>> > -             sqlite3_snprintf(sizeof(zTab), zTab, "_sql_stat%d", i);
>> > -             if (sqlite3FindTable(pParse->db, zTab)) {
>> > -                     sqlite3NestedParse(pParse,
>> > -                                        "DELETE FROM \"%s\" WHERE
>> \"%s\"=%Q",
>> > -                                        zTab, zType, zName);
>> > -             }
>> > -     }
>> > +    int i, j;
>>
>> You don’t need to declare vars beforehand:
>> it is is required in obsolete C standards (such as KR or C89).
>> However, we are using *modern* C99:
>> for (int i = 0; …)  - is OK.
>>
>> > +    if(strcmp(zType, "idx") == 0)
>>
>> As you suggest, you can get rid of this ’type’. Instead, just
>> check index name on nullability.
>>
>> > +        for(i = 1, j = 1; i <= 2; i++, j++) {
>>
>> This cycle-for is completely unreadable. Don’t make things to be
>> complicated:
>> it is better to use *less* beautiful, but more obvious and clear approach.
>> Don’t be afraid of changing code: this function is declared as static,
>> so it is not available for public usage.
>>
>> I would like to suggest you to get rid of cycle and snprintf,
>> but add two almost the same calls of sqlite3NestedParse().
>> It will result in plain and readable code:
>> sqlite3NestedParse(…, ” … WHERE tbl = stat1”);
>> sqlite3NestedParse(…, ” … WHERE tbl = stat4”);
>>
>> > +            char zTab[24];
>> > +            sqlite3_snprintf(sizeof(zTab), zTab, "_sql_stat%d", i * j);
>> > +            sqlite3NestedParse(pParse,
>> > +                        "DELETE FROM \"%s\" WHERE (\"idx\"=%Q AND "
>> > +                        "\"tbl\"=%Q)",
>> > +                        zTab, idx_name, table_name);
>> > +        }
>> > +    else
>> > +        for(i = 1, j = 1; i <= 2; i++, j++) {
>> > +            char zTab[24];
>> > +            sqlite3_snprintf(sizeof(zTab), zTab, "_sql_stat%d", i * j);
>> > +            sqlite3NestedParse(pParse,
>> > +                        "DELETE FROM \"%s\" WHERE \"tbl\"=%Q",
>> > +                        zTab, table_name);
>> > +        }
>> > }
>> >
>> > /*
>> > @@ -2415,7 +2424,7 @@ sqlite3DropTable(Parse * pParse, SrcList * pName,
>> int isView, int noErr)
>> >        */
>> >
>> >       sqlite3BeginWriteOperation(pParse, 1);
>> > -     sqlite3ClearStatTables(pParse, "tbl", pTab->zName);
>> > +    sql_clear_stat_tables(pParse, "tbl", pTab->zName, NULL);
>> >       sqlite3FkDropTable(pParse, pName, pTab);
>> >       sqlite3CodeDropTable(pParse, pTab, isView);
>> >
>> > @@ -3417,7 +3426,7 @@ sqlite3DropIndex(Parse * pParse, SrcList * pName,
>> Token * pName2, int ifExists)
>> >        * But firstly, delete statistics since schema
>> >        * changes after DDL.
>> >        */
>> > -     sqlite3ClearStatTables(pParse, "idx", pIndex->zName);
>> > +    sql_clear_stat_tables(pParse, "idx", pIndex->pTable->zName,
>> pIndex->zName);
>> >       int record_reg = ++pParse->nMem;
>> >       int space_id_reg = ++pParse->nMem;
>> >       sqlite3VdbeAddOp2(v, OP_Integer,
>> SQLITE_PAGENO_TO_SPACEID(pIndex->tnum),
>> > diff --git a/test/sql/sql-statN-index-drop.result
>> b/test/sql/sql-statN-index-drop.result
>> > new file mode 100644
>> > index 0000000..c7e476f
>> > --- /dev/null
>> > +++ b/test/sql/sql-statN-index-drop.result
>> > @@ -0,0 +1,127 @@
>> > +test_run = require('test_run').new()
>> > +---
>> > +...
>> > +-- Initializing some things.
>> > +box.sql.execute("CREATE TABLE t1(id PRIMARY KEY, a);")
>> > +---
>> > +...
>> > +box.sql.execute("CREATE TABLE t2(id PRIMARY KEY, a);")
>> > +---
>> > +...
>> > +box.sql.execute("CREATE INDEX i1 ON t1(a);")
>> > +---
>> > +...
>> > +box.sql.execute("CREATE INDEX i1 ON t2(a);")
>> > +---
>> > +...
>> > +box.sql.execute("INSERT INTO t1 VALUES(1, 2);")
>> > +---
>> > +...
>> > +box.sql.execute("INSERT INTO t2 VALUES(1, 2);")
>> > +---
>> > +...
>> > +-- Analyze.
>> > +box.sql.execute("ANALYZE;")
>> > +---
>> > +...
>> > +-- Checking the data.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +---
>> > +- - ['T1', 'I1', '1', '0', '0', !!binary kQI=]
>> > +  - ['T1', 'T1', '1', '0', '0', !!binary kQE=]
>> > +  - ['T2', 'I1', '1', '0', '0', !!binary kQI=]
>> > +  - ['T2', 'T2', '1', '0', '0', !!binary kQE=]
>> > +...
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +---
>> > +- - ['T1', 'I1', '1 1']
>> > +  - ['T1', 'T1', '1 1']
>> > +  - ['T2', 'I1', '1 1']
>> > +  - ['T2', 'T2', '1 1']
>> > +...
>> > +-- Dropping an index.
>> > +box.sql.execute("DROP INDEX i1 ON t1;")
>> > +---
>> > +...
>> > +-- Checking the DROP INDEX results.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +---
>> > +- - ['T1', 'T1', '1', '0', '0', !!binary kQE=]
>> > +  - ['T2', 'I1', '1', '0', '0', !!binary kQI=]
>> > +  - ['T2', 'T2', '1', '0', '0', !!binary kQE=]
>> > +...
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +---
>> > +- - ['T1', 'T1', '1 1']
>> > +  - ['T2', 'I1', '1 1']
>> > +  - ['T2', 'T2', '1 1']
>> > +...
>> > +--Cleaning up.
>> > +box.sql.execute("DROP TABLE t1;")
>> > +---
>> > +...
>> > +box.sql.execute("DROP TABLE t2;")
>> > +---
>> > +...
>> > +-- Same test but dropping an INDEX ON t2.
>> > +box.sql.execute("CREATE TABLE t1(id PRIMARY KEY, a);")
>> > +---
>> > +...
>> > +box.sql.execute("CREATE TABLE t2(id PRIMARY KEY, a);")
>> > +---
>> > +...
>> > +box.sql.execute("CREATE INDEX i1 ON t1(a);")
>> > +---
>> > +...
>> > +box.sql.execute("CREATE INDEX i1 ON t2(a);")
>> > +---
>> > +...
>> > +box.sql.execute("INSERT INTO t1 VALUES(1, 2);")
>> > +---
>> > +...
>> > +box.sql.execute("INSERT INTO t2 VALUES(1, 2);")
>> > +---
>> > +...
>> > +-- Analyze.
>> > +box.sql.execute("ANALYZE;")
>> > +---
>> > +...
>> > +-- Checking the data.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +---
>> > +- - ['T1', 'I1', '1', '0', '0', !!binary kQI=]
>> > +  - ['T1', 'T1', '1', '0', '0', !!binary kQE=]
>> > +  - ['T2', 'I1', '1', '0', '0', !!binary kQI=]
>> > +  - ['T2', 'T2', '1', '0', '0', !!binary kQE=]
>> > +...
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +---
>> > +- - ['T1', 'I1', '1 1']
>> > +  - ['T1', 'T1', '1 1']
>> > +  - ['T2', 'I1', '1 1']
>> > +  - ['T2', 'T2', '1 1']
>> > +...
>> > +-- Dropping an index.
>> > +box.sql.execute("DROP INDEX i1 ON t2;")
>> > +---
>> > +...
>> > +-- Checking the DROP INDEX results.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +---
>> > +- - ['T1', 'I1', '1', '0', '0', !!binary kQI=]
>> > +  - ['T1', 'T1', '1', '0', '0', !!binary kQE=]
>> > +  - ['T2', 'T2', '1', '0', '0', !!binary kQE=]
>> > +...
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +---
>> > +- - ['T1', 'I1', '1 1']
>> > +  - ['T1', 'T1', '1 1']
>> > +  - ['T2', 'T2', '1 1']
>> > +...
>> > +--Cleaning up.
>> > +box.sql.execute("DROP TABLE t1;")
>> > +---
>> > +...
>> > +box.sql.execute("DROP TABLE t2;")
>> > +---
>> > +...
>> > diff --git a/test/sql/sql-statN-index-drop.test.lua
>> b/test/sql/sql-statN-index-drop.test.lua
>> > new file mode 100644
>> > index 0000000..bf4a752
>> > --- /dev/null
>> > +++ b/test/sql/sql-statN-index-drop.test.lua
>> > @@ -0,0 +1,54 @@
>> > +test_run = require('test_run').new()
>> > +
>> > +-- Initializing some things.
>> > +box.sql.execute("CREATE TABLE t1(id PRIMARY KEY, a);")
>> > +box.sql.execute("CREATE TABLE t2(id PRIMARY KEY, a);")
>> > +box.sql.execute("CREATE INDEX i1 ON t1(a);")
>> > +box.sql.execute("CREATE INDEX i1 ON t2(a);")
>> > +box.sql.execute("INSERT INTO t1 VALUES(1, 2);")
>> > +box.sql.execute("INSERT INTO t2 VALUES(1, 2);")
>> > +
>> > +-- Analyze.
>> > +box.sql.execute("ANALYZE;")
>> > +
>> > +-- Checking the data.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +
>> > +-- Dropping an index.
>> > +box.sql.execute("DROP INDEX i1 ON t1;")
>> > +
>> > +-- Checking the DROP INDEX results.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +
>> > +--Cleaning up.
>> > +box.sql.execute("DROP TABLE t1;")
>> > +box.sql.execute("DROP TABLE t2;")
>> > +
>> > +-- Same test but dropping an INDEX ON t2.
>> > +
>> > +box.sql.execute("CREATE TABLE t1(id PRIMARY KEY, a);")
>> > +box.sql.execute("CREATE TABLE t2(id PRIMARY KEY, a);")
>> > +box.sql.execute("CREATE INDEX i1 ON t1(a);")
>> > +box.sql.execute("CREATE INDEX i1 ON t2(a);")
>> > +box.sql.execute("INSERT INTO t1 VALUES(1, 2);")
>> > +box.sql.execute("INSERT INTO t2 VALUES(1, 2);")
>> > +
>> > +-- Analyze.
>> > +box.sql.execute("ANALYZE;")
>> > +
>> > +-- Checking the data.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +
>> > +-- Dropping an index.
>> > +box.sql.execute("DROP INDEX i1 ON t2;")
>> > +
>> > +-- Checking the DROP INDEX results.
>> > +box.sql.execute("SELECT * FROM \"_sql_stat4\";")
>> > +box.sql.execute("SELECT * FROM \"_sql_stat1\";")
>> > +
>> > +--Cleaning up.
>> > +box.sql.execute("DROP TABLE t1;")
>> > +box.sql.execute("DROP TABLE t2;")
>> > --
>> > 2.7.4
>> >
>> >
>>
>> Suggested changes were applied so this is diff:
>
>
> diff --git a/src/box/sql/build.c b/src/box/sql/build.c
> index 44d7548..16ae042 100644
> --- a/src/box/sql/build.c
> +++ b/src/box/sql/build.c
> @@ -2206,34 +2206,35 @@ sqliteViewResetAll(sqlite3 * db)
>  #define sqliteViewResetAll(A,B)
>  #endif /* SQLITE_OMIT_VIEW */
>
> -/*
> +/**
>   * Remove entries from the _sql_statN tables (for N in (1, 4))
>   * after a DROP INDEX or DROP TABLE command.
> + *
> + * @param table_name table to be dropped or
> + *                   the table that contains index to be dropped
> + * @param idx_name index to be dropped
>
>
> Nitpicking: put dot at the end of comments and
> start sentences from capital letter.
> (This is just advice. You may skip most ’nitpicking’ comments.)
>
> Moreover, you forget to describe first arg:
> even despite the fact that it is obviously ’The parsing context'.
>
>   */
>  static void
> -sql_clear_stat_tables(Parse * pParse, /* The parsing context */
> -        const char *zType,     /* "idx" or "tbl" */
> -               const char *table_name,  /* Name of the table*/
> -        const char *idx_name /* Name of the index*/
> -    )
> +sql_clear_stat_tables(Parse *parse,
> +               const char *table_name,
> +        const char *idx_name)
>
>
> You don’t need to place each arg at new line.
> The only restriction is 80 chars per line.
>
>  {
> -    int i, j;
> -    if(strcmp(zType, "idx") == 0)
> -        for(i = 1, j = 1; i <= 2; i++, j++) {
> -            char zTab[24];
> -            sqlite3_snprintf(sizeof(zTab), zTab, "_sql_stat%d", i * j);
> -            sqlite3NestedParse(pParse,
> -                        "DELETE FROM \"%s\" WHERE (\"idx\"=%Q AND "
> -                        "\"tbl\"=%Q)",
> -                        zTab, idx_name, table_name);
> -        }
> -    else
> -        for(i = 1, j = 1; i <= 2; i++, j++) {
> -            char zTab[24];
> -            sqlite3_snprintf(sizeof(zTab), zTab, "_sql_stat%d", i * j);
> -            sqlite3NestedParse(pParse,
> -                        "DELETE FROM \"%s\" WHERE \"tbl\"=%Q",
> -                        zTab, table_name);
> +    if(idx_name) {
>
>
> It is better to use explicit == NULL check.
>
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat1\" WHERE (\"idx\"=%Q AND "
> +                    "\"tbl\"=%Q)",
> +                    idx_name, table_name);
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat4\" WHERE (\"idx\"=%Q AND "
> +                    "\"tbl\"=%Q)",
> +                    idx_name, table_name);
> +    } else {
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat1\" WHERE \"tbl\"=%Q",
> +                    table_name);
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat4\" WHERE \"tbl\"=%Q",
> +                    table_name);
>          }
>  }
>
> @@ -2424,7 +2425,7 @@ sqlite3DropTable(Parse * pParse, SrcList * pName,
> int isView, int noErr)
>   */
>
>   sqlite3BeginWriteOperation(pParse, 1);
> -    sql_clear_stat_tables(pParse, "tbl", pTab->zName, NULL);
> +    sql_clear_stat_tables(pParse, pTab->zName, NULL);
>   sqlite3FkDropTable(pParse, pName, pTab);
>   sqlite3CodeDropTable(pParse, pTab, isView);
>
> @@ -3426,7 +3427,7 @@ sqlite3DropIndex(Parse * pParse, SrcList * pName,
> Token * pName2, int ifExists)
>   * But firstly, delete statistics since schema
>   * changes after DDL.
>   */
> -    sql_clear_stat_tables(pParse, "idx", pIndex->pTable->zName,
> pIndex->zName);
> +    sql_clear_stat_tables(pParse, pIndex->pTable->zName, pIndex->zName);
>   int record_reg = ++pParse->nMem;
>   int space_id_reg = ++pParse->nMem;
>   sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_PAGENO_TO_SPACEID(pIndex->tnum),
> diff --git a/test/xlog/checkpoint_daemon.result
> b/test/xlog/checkpoint_daemon.result
> index d5ed666..1c28336 100644
> --- a/test/xlog/checkpoint_daemon.result
> +++ b/test/xlog/checkpoint_daemon.result
> @@ -96,11 +96,11 @@ fiber.sleep(3 * PERIOD)
>  -- check that it's not first snapshot
>  test_run:grep_log("default", "saving snapshot", 400) == nil
>  ---
> -- true
> +- false
>  ...
>  test_run:grep_log("default", "making snapshot", 400) ~= nil
>  ---
> -- true
> +- false
>
>
> I guess, this diff doesn’t belong to the patch.
>
>  ...
>  -- restore default options
>  box.cfg{checkpoint_interval = 3600 * 4, checkpoint_count = 4 }
>
>
>
> Diff after the changes:

diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index 16ae042..958927e 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -2210,16 +2210,17 @@ sqliteViewResetAll(sqlite3 * db)
  * Remove entries from the _sql_statN tables (for N in (1, 4))
  * after a DROP INDEX or DROP TABLE command.
  *
- * @param table_name table to be dropped or
- *                   the table that contains index to be dropped
- * @param idx_name index to be dropped
+ * @param parse      The parsing context.
+ * @param table_name The table to be dropped or
+ *                   the table that contains index to be dropped.
+ * @param idx_name   Index to be dropped.
  */
 static void
-sql_clear_stat_tables(Parse *parse,
-               const char *table_name,
-        const char *idx_name)
+sql_clear_stat_tables(Parse *parse, const char *table_name,
+                      const char *idx_name
+                     )
 {
-    if(idx_name) {
+    if(idx_name != NULL) {
         sqlite3NestedParse(parse,
                     "DELETE FROM \"_sql_stat1\" WHERE (\"idx\"=%Q AND "
                     "\"tbl\"=%Q)",
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.tarantool.org/pipermail/tarantool-patches/attachments/20180404/064b6628/attachment.html>


More information about the Tarantool-patches mailing list