Parser, SQL: table-specific FOR SYSTEM_TIME [closes #116]

* Syntax sugar: query-global QUERY FOR SYSTEM_TIME

mysql-test/suite/versioning/r/optimized_fields.result

@@ -25,7 +25,7 @@ a	b
 3	NULL
 Warnings:
 Warning	4075	Attempt to read unversioned field `b` in historical query
-select count(*) from t group by b for system_time as of timestamp now(6);
+select count(*) from t group by b query for system_time as of timestamp now(6);
 count(*)
 2
 Warnings:
@@ -42,23 +42,23 @@ a	b
 3	NULL
 Warnings:
 Warning	4075	Attempt to read unversioned field `b` in historical query
-select * from t group by a having a=2 for system_time as of timestamp now(6);
+select * from t group by a having a=2 query for system_time as of timestamp now(6);
 a	b
 Warnings:
 Warning	4075	Attempt to read unversioned field `b` in historical query
-select * from t group by b having b=2 for system_time as of timestamp now(6);
+select * from t group by b having b=2 query for system_time as of timestamp now(6);
 a	b
 Warnings:
 Warning	4075	Attempt to read unversioned field `b` in historical query
-select a from t where b=2 for system_time as of timestamp now(6);
+select a from t where b=2 query for system_time as of timestamp now(6);
 a
 Warnings:
 Warning	4075	Attempt to read unversioned field `b` in historical query
-select a from t where b=NULL for system_time as of timestamp now(6);
+select a from t where b=NULL query for system_time as of timestamp now(6);
 a
 Warnings:
 Warning	4075	Attempt to read unversioned field `b` in historical query
-select count(*), b from t group by b having b=NULL for system_time as of timestamp now(6);
+select count(*), b from t group by b having b=NULL query for system_time as of timestamp now(6);
 count(*)	b
 Warnings:
 Warning	4075	Attempt to read unversioned field `b` in historical query

mysql-test/suite/versioning/r/select.result

@@ -95,11 +95,11 @@ select t1.x as RJ1_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 right join t2
 delete from t1;
 delete from t2;
 select t1.x as IJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 inner join t2 on t1.x = t2.x
-for system_time as of timestamp @t0;  
+query for system_time as of timestamp @t0;
 select t1.x as LJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 left join t2 on t1.x = t2.x
-for system_time as of timestamp @t0;
+query for system_time as of timestamp @t0;
 select t1.x as RJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 right join t2 on t1.x = t2.x
-for system_time as of timestamp @t0;
+query for system_time as of timestamp @t0;
 drop table t1;
 drop table t2;
 end~~

mysql-test/suite/versioning/r/view.result

@@ -23,7 +23,7 @@ x
 create or replace view vt1 as select * from t1;
 show create view vt1;
 View	Create View	character_set_client	collation_connection
-vt1	CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `vt1` AS select `t1`.`x` AS `x` from `t1` where `t1`.`sys_trx_end` = 18446744073709551615 for system_time all 	latin1	latin1_swedish_ci
+vt1	CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `vt1` AS select `t1`.`x` AS `x` from `t1` where `t1`.`sys_trx_end` = 18446744073709551615 query for system_time all 	latin1	latin1_swedish_ci
 drop view vt1;
 drop view vt2;
 drop table t1;

mysql-test/suite/versioning/t/optimized_fields.test

@@ -9,14 +9,14 @@ select * from t;
 select a from t for system_time as of timestamp now(6);
 select a, b, b+0 from t for system_time as of timestamp now(6);
 select * from t for system_time as of timestamp now(6);
-select count(*) from t group by b for system_time as of timestamp now(6);
+select count(*) from t group by b query for system_time as of timestamp now(6);
 select * from t for system_time as of timestamp now(6) order by b asc;
 select * from t for system_time as of timestamp now(6) order by b desc;
-select * from t group by a having a=2 for system_time as of timestamp now(6);
-select * from t group by b having b=2 for system_time as of timestamp now(6);
-select a from t where b=2 for system_time as of timestamp now(6);
-select a from t where b=NULL for system_time as of timestamp now(6);
-select count(*), b from t group by b having b=NULL for system_time as of timestamp now(6);
+select * from t group by a having a=2 query for system_time as of timestamp now(6);
+select * from t group by b having b=2 query for system_time as of timestamp now(6);
+select a from t where b=2 query for system_time as of timestamp now(6);
+select a from t where b=NULL query for system_time as of timestamp now(6);
+select count(*), b from t group by b having b=NULL query for system_time as of timestamp now(6);
 select a, b from t;
 
 drop table t;

mysql-test/suite/versioning/t/select.test

@@ -91,11 +91,11 @@ begin
   delete from t2;
 
   select t1.x as IJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 inner join t2 on t1.x = t2.x
-  for system_time as of timestamp @t0;  
+  query for system_time as of timestamp @t0;
   select t1.x as LJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 left join t2 on t1.x = t2.x
-  for system_time as of timestamp @t0;
+  query for system_time as of timestamp @t0;
   select t1.x as RJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 right join t2 on t1.x = t2.x
-  for system_time as of timestamp @t0;
+  query for system_time as of timestamp @t0;
 
   drop table t1;
   drop table t2;

sql/item.cc

@@ -2762,8 +2762,10 @@ void Item_field::set_field(Field *field_par)
 
   field->force_null= false;
   if (field->flags & VERS_OPTIMIZED_UPDATE_FLAG && context &&
-      context->select_lex &&
-      context->select_lex->vers_conditions.type != FOR_SYSTEM_TIME_UNSPECIFIED)
+      ((field->table->pos_in_table_list &&
+      field->table->pos_in_table_list->vers_conditions.type != FOR_SYSTEM_TIME_UNSPECIFIED) ||
+      (context->select_lex &&
+      context->select_lex->vers_conditions.type != FOR_SYSTEM_TIME_UNSPECIFIED)))
   {
     field->force_null= true;
     push_warning_printf(

sql/sql_lex.cc

@@ -766,6 +766,8 @@ void LEX::start(THD *thd_arg)
   frame_bottom_bound= NULL;
   win_spec= NULL;
 
+  vers_conditions.empty();
+
   is_lex_started= TRUE;
   DBUG_VOID_RETURN;
 }
@@ -1366,6 +1368,19 @@ int MYSQLlex(YYSTYPE *yylval, THD *thd)
       return FOR_SYM;
     }
     break;
+  case QUERY_SYM:
+    token= lex_one_token(yylval, thd);
+    lip->add_digest_token(token, yylval);
+    switch(token) {
+    case FOR_SYM:
+      return QUERY_FOR_SYM;
+    default:
+      lip->lookahead_yylval= lip->yylval;
+      lip->yylval= NULL;
+      lip->lookahead_token= token;
+      return QUERY_SYM;
+    }
+    break;
   default:
     break;
   }

sql/sql_lex.h

@@ -2920,6 +2920,9 @@ struct LEX: public Query_tables_list
   Window_frame_bound *frame_bottom_bound;
   Window_spec *win_spec;
 
+  /* System Versioning */
+  vers_select_conds_t vers_conditions;
+
   inline void free_set_stmt_mem_root()
   {
     DBUG_ASSERT(!is_arena_for_set_stmt());

sql/sql_select.cc

@@ -688,42 +688,21 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
   {
     if (table->table && table->table->versioned())
       versioned_tables++;
-  }
-
-  vers_range_type_t query_type= slex->vers_conditions.type;
-
-  if (versioned_tables == 0)
-  {
-    if (query_type != FOR_SYSTEM_TIME_UNSPECIFIED)
+    else if (table->vers_conditions.type != FOR_SYSTEM_TIME_UNSPECIFIED)
     {
       my_error(ER_VERSIONING_REQUIRED, MYF(0), "`FOR SYSTEM_TIME` query");
       DBUG_RETURN(-1);
     }
-    DBUG_RETURN(0);
   }
 
-  if (query_type != FOR_SYSTEM_TIME_UNSPECIFIED)
+  if (versioned_tables == 0)
   {
-    switch (slex->lock_type)
+    if (slex->vers_conditions.type != FOR_SYSTEM_TIME_UNSPECIFIED)
     {
-    case TL_WRITE_ALLOW_WRITE:
-    case TL_WRITE_CONCURRENT_INSERT:
-    case TL_WRITE_DELAYED:
-    case TL_WRITE_DEFAULT:
-    case TL_WRITE_LOW_PRIORITY:
-    case TL_WRITE:
-    case TL_WRITE_ONLY:
-      my_error(ER_VERS_WRONG_PARAMS, MYF(0), "FOR SYSTEM_TIME query", "write-locking of historic rows");
+      my_error(ER_VERSIONING_REQUIRED, MYF(0), "`FOR SYSTEM_TIME` query");
       DBUG_RETURN(-1);
-    default:
-      break;
-    }
-
-    if (query_type == FOR_SYSTEM_TIME_ALL)
-    {
-      slex->vers_conditions.unwrapped= true;
-      DBUG_RETURN(0);
     }
+    DBUG_RETURN(0);
   }
 
   /* For prepared statements we create items on statement arena,
@@ -779,6 +758,36 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
   {
     if (table->table && table->table->versioned())
     {
+      vers_select_conds_t &vers_conditions=
+        table->vers_conditions.type == FOR_SYSTEM_TIME_UNSPECIFIED ?
+          slex->vers_conditions : table->vers_conditions;
+
+      if (vers_conditions.type != FOR_SYSTEM_TIME_UNSPECIFIED)
+      {
+        switch (slex->lock_type)
+        {
+        case TL_WRITE_ALLOW_WRITE:
+        case TL_WRITE_CONCURRENT_INSERT:
+        case TL_WRITE_DELAYED:
+        case TL_WRITE_DEFAULT:
+        case TL_WRITE_LOW_PRIORITY:
+        case TL_WRITE:
+        case TL_WRITE_ONLY:
+          my_error(ER_VERS_WRONG_PARAMS, MYF(0), "FOR SYSTEM_TIME query", "write-locking of historic rows");
+          if (arena)
+            thd->restore_active_arena(arena, &backup);
+          DBUG_RETURN(-1);
+        default:
+          break;
+        }
+
+        if (vers_conditions.type == FOR_SYSTEM_TIME_ALL)
+        {
+          vers_conditions.unwrapped= true;
+          continue;
+        }
+      }
+
       COND** dst_cond= where_expr;
       if (table->on_expr)
       {
@@ -798,14 +807,14 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
 
       if (table->table->versioned_by_sql())
       {
-        if (slex->vers_conditions.unit == UNIT_TRX_ID)
+        if (vers_conditions.unit == UNIT_TRX_ID)
         {
           my_error(ER_VERS_ENGINE_UNSUPPORTED, MYF(0), table->table_name);
           DBUG_RETURN(-1);
         }
       }
-      else if (vers_simple_select && slex->vers_conditions.unit == UNIT_TIMESTAMP
-          && query_type != FOR_SYSTEM_TIME_UNSPECIFIED)
+      else if (vers_simple_select && vers_conditions.unit == UNIT_TIMESTAMP
+          && vers_conditions.type != FOR_SYSTEM_TIME_UNSPECIFIED)
       {
         DBUG_ASSERT(table->table->s && table->table->s->db_plugin);
         handlerton *hton= plugin_hton(table->table->s->db_plugin);
@@ -826,7 +835,7 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
       Item *cond1= 0, *cond2= 0, *curr= 0;
       if (table->table->versioned_by_sql() || vers_simple_select)
       {
-        switch (query_type)
+        switch (vers_conditions.type)
         {
         case FOR_SYSTEM_TIME_UNSPECIFIED:
           if (table->table->versioned_by_sql())
@@ -844,21 +853,21 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
           break;
         case FOR_SYSTEM_TIME_AS_OF:
           cond1= newx Item_func_le(thd, row_start,
-            slex->vers_conditions.start);
+            vers_conditions.start);
           cond2= newx Item_func_gt(thd, row_end,
-            slex->vers_conditions.start);
+            vers_conditions.start);
           break;
         case FOR_SYSTEM_TIME_FROM_TO:
           cond1= newx Item_func_lt(thd, row_start,
-            slex->vers_conditions.end);
+            vers_conditions.end);
           cond2= newx Item_func_ge(thd, row_end,
-            slex->vers_conditions.start);
+            vers_conditions.start);
           break;
         case FOR_SYSTEM_TIME_BETWEEN:
           cond1= newx Item_func_le(thd, row_start,
-            slex->vers_conditions.end);
+            vers_conditions.end);
           cond2= newx Item_func_ge(thd, row_end,
-            slex->vers_conditions.start);
+            vers_conditions.start);
           break;
         default:
           DBUG_ASSERT(0);
@@ -872,33 +881,33 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
 
         Item *trx_id0, *trx_id1;
 
-        switch (query_type)
+        switch (vers_conditions.type)
         {
         case FOR_SYSTEM_TIME_UNSPECIFIED:
           curr= newx Item_int(thd, ULONGLONG_MAX);
           cond1= newx Item_func_eq(thd, row_end2, curr);
           break;
         case FOR_SYSTEM_TIME_AS_OF:
-          trx_id0= slex->vers_conditions.unit == UNIT_TIMESTAMP ?
-            newx Item_func_vtq_id(thd, slex->vers_conditions.start, VTQ_TRX_ID) :
-            slex->vers_conditions.start;
+          trx_id0= vers_conditions.unit == UNIT_TIMESTAMP ?
+            newx Item_func_vtq_id(thd, vers_conditions.start, VTQ_TRX_ID) :
+            vers_conditions.start;
           cond1= newx Item_func_vtq_trx_sees_eq(thd, trx_id0, row_start);
           cond2= newx Item_func_vtq_trx_sees(thd, row_end, trx_id0);
           break;
         case FOR_SYSTEM_TIME_FROM_TO:
         case FOR_SYSTEM_TIME_BETWEEN:
-          if (slex->vers_conditions.unit == UNIT_TIMESTAMP)
+          if (vers_conditions.unit == UNIT_TIMESTAMP)
           {
-            trx_id0= newx Item_func_vtq_id(thd, slex->vers_conditions.start, VTQ_TRX_ID, true);
-            trx_id1= newx Item_func_vtq_id(thd, slex->vers_conditions.end, VTQ_TRX_ID, false);
+            trx_id0= newx Item_func_vtq_id(thd, vers_conditions.start, VTQ_TRX_ID, true);
+            trx_id1= newx Item_func_vtq_id(thd, vers_conditions.end, VTQ_TRX_ID, false);
           }
           else
           {
-            trx_id0= slex->vers_conditions.start;
-            trx_id1= slex->vers_conditions.end;
+            trx_id0= vers_conditions.start;
+            trx_id1= vers_conditions.end;
           }
 
-          cond1= query_type == FOR_SYSTEM_TIME_FROM_TO ?
+          cond1= vers_conditions.type == FOR_SYSTEM_TIME_FROM_TO ?
             newx Item_func_vtq_trx_sees(thd, trx_id1, row_start) :
             newx Item_func_vtq_trx_sees_eq(thd, trx_id1, row_start);
           cond2= newx Item_func_vtq_trx_sees_eq(thd, row_end, trx_id0);
@@ -925,9 +934,7 @@ int vers_setup_select(THD *thd, TABLE_LIST *tables, COND **where_expr,
   } // for (table= tables; ...)
 
   if (arena)
-  {
     thd->restore_active_arena(arena, &backup);
-  }
 
   slex->vers_conditions.unwrapped= true;
 
@@ -25554,7 +25561,7 @@ void st_select_lex::print(THD *thd, String *str, enum_query_type query_type)
   if (vers_conditions.unwrapped)
   {
     // versioning conditions are already unwrapped to WHERE clause
-    str->append(STRING_WITH_LEN(" for system_time all "));
+    str->append(STRING_WITH_LEN(" query for system_time all "));
   }
 
   if (order_list.elements)

sql/sql_yacc.yy

@@ -751,6 +751,7 @@ Virtual_column_info *add_virtual_expression(THD *thd, Item *expr)
 
 %}
 %union {
+  bool BOOL;
   int  num;
   ulong ulong_num;
   ulonglong ulonglong_number;
@@ -1352,6 +1353,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
 %token  PURGE
 %token  QUARTER_SYM
 %token  QUERY_SYM
+%token  QUERY_FOR_SYM                 /* INTERNAL */
 %token  QUICK
 %token  RAISE_SYM                     /* Oracle-PLSQL-R */
 %token  RANGE_SYM                     /* SQL-2003-R */
@@ -1970,6 +1972,7 @@ END_OF_INPUT
 %type <lex_str_list> opt_with_column_list
 
 %type <vers_range_unit> trans_or_timestamp
+%type <BOOL> opt_for_system_time_clause
 
 %%
 
@@ -8762,7 +8765,7 @@ table_expression:
           opt_group_clause
           opt_having_clause
           opt_window_clause
-          opt_for_system_time_clause
+          opt_query_for_system_time_clause
         ;
 
 opt_table_expression:
@@ -8808,75 +8811,74 @@ trans_or_timestamp:
           }
         ;
 
-opt_for_system_time_clause:
+opt_query_for_system_time_clause:
           /* empty */
           {}
-        | FOR_SYSTEM_TIME_SYM
-          AS OF_SYM
-          trans_or_timestamp simple_expr
+        | QUERY_FOR_SYM SYSTEM_TIME_SYM for_system_time_expr
+          {
+            DBUG_ASSERT(Select);
+            Select->vers_conditions= Lex->vers_conditions;
+          }
+        ;
+
+opt_for_system_time_clause:
+          /* empty */
+          {
+            $$= false;
+          }
+        | FOR_SYSTEM_TIME_SYM for_system_time_expr
+          {
+            $$= true;
+          }
+        ;
+
+for_system_time_expr:
+          AS OF_SYM trans_or_timestamp simple_expr
           {
-            Lex->current_select->vers_conditions.init(FOR_SYSTEM_TIME_AS_OF, $4, $5);
+            Lex->vers_conditions.init(FOR_SYSTEM_TIME_AS_OF, $3, $4);
           }
-        | FOR_SYSTEM_TIME_SYM
-          AS OF_SYM
-          NOW_SYM
+        | AS OF_SYM NOW_SYM
           {
             Item *item= new (thd->mem_root) Item_func_now_local(thd, 6);
             if (item == NULL)
               MYSQL_YYABORT;
-            Lex->current_select->vers_conditions.init(FOR_SYSTEM_TIME_AS_OF, UNIT_TIMESTAMP, item);
+            Lex->vers_conditions.init(FOR_SYSTEM_TIME_AS_OF, UNIT_TIMESTAMP, item);
           }
-        | FOR_SYSTEM_TIME_SYM ALL
+        | ALL
           {
-            Lex->current_select->vers_conditions.init(FOR_SYSTEM_TIME_ALL, UNIT_TIMESTAMP);
+            Lex->vers_conditions.init(FOR_SYSTEM_TIME_ALL, UNIT_TIMESTAMP);
           }
-        | FOR_SYSTEM_TIME_SYM
-          FROM
-          trans_or_timestamp
-          simple_expr
-          TO_SYM
-          trans_or_timestamp
-          simple_expr
+        | FROM trans_or_timestamp simple_expr
+          TO_SYM trans_or_timestamp simple_expr
           {
-            if ($3 != $6)
+            if ($2 != $5)
             {
               Lex->parse_error(ER_VERS_RANGE_UNITS_MISMATCH);
               MYSQL_YYABORT;
             }
-            Lex->current_select->vers_conditions.init(FOR_SYSTEM_TIME_FROM_TO, $3, $4, $7);
+            Lex->vers_conditions.init(FOR_SYSTEM_TIME_FROM_TO, $2, $3, $6);
           }
-        | FOR_SYSTEM_TIME_SYM
-          trans_or_timestamp
-          FROM
-          simple_expr
-          TO_SYM
-          simple_expr
+        | trans_or_timestamp
+          FROM simple_expr
+          TO_SYM simple_expr
           {
-            Lex->current_select->vers_conditions.init(FOR_SYSTEM_TIME_FROM_TO, $2, $4, $6);
+            Lex->vers_conditions.init(FOR_SYSTEM_TIME_FROM_TO, $1, $3, $5);
           }
-        | FOR_SYSTEM_TIME_SYM
-          BETWEEN_SYM
-          trans_or_timestamp
-          simple_expr
-          AND_SYM
-          trans_or_timestamp
-          simple_expr
+        | BETWEEN_SYM trans_or_timestamp simple_expr
+          AND_SYM trans_or_timestamp simple_expr
           {
-            if ($3 != $6)
+            if ($2 != $5)
             {
               Lex->parse_error(ER_VERS_RANGE_UNITS_MISMATCH);
               MYSQL_YYABORT;
             }
-            Lex->current_select->vers_conditions.init(FOR_SYSTEM_TIME_BETWEEN, $3, $4, $7);
+            Lex->vers_conditions.init(FOR_SYSTEM_TIME_BETWEEN, $2, $3, $6);
           }
-        | FOR_SYSTEM_TIME_SYM
-          trans_or_timestamp
-          BETWEEN_SYM
-          simple_expr
-          AND_SYM
-          simple_expr
+        | trans_or_timestamp
+          BETWEEN_SYM simple_expr
+          AND_SYM simple_expr
           {
-            Lex->current_select->vers_conditions.init(FOR_SYSTEM_TIME_BETWEEN, $2, $4, $6);
+            Lex->vers_conditions.init(FOR_SYSTEM_TIME_BETWEEN, $1, $3, $5);
           }
         ;
 
@@ -11284,10 +11286,11 @@ table_factor:
 
 table_primary_ident:
           {
+            DBUG_ASSERT(Select);
             SELECT_LEX *sel= Select;
             sel->table_join_options= 0;
           }
-          table_ident opt_use_partition opt_table_alias opt_key_definition
+          table_ident opt_use_partition opt_table_alias opt_key_definition opt_for_system_time_clause
           {
             if (!($$= Select->add_table_to_list(thd, $2, $4,
                                                 Select->get_table_join_options(),
@@ -11297,6 +11300,8 @@ table_primary_ident:
                                                 $3)))
               MYSQL_YYABORT;
             Select->add_joined_table($$);
+            if ($6)
+              $$->vers_conditions= Lex->vers_conditions;
           }
         ;
 
@@ -13007,6 +13012,8 @@ truncate:
             lex->m_sql_cmd= new (thd->mem_root) Sql_cmd_truncate_table();
             if (lex->m_sql_cmd == NULL)
               MYSQL_YYABORT;
+            if ($5)
+              Select->vers_conditions= Lex->vers_conditions;
           }
         ;
 

sql/table.h

@@ -1856,7 +1856,7 @@ enum vers_range_unit_t
   UNIT_TRX_ID
 };
 
-/** System versioning support. */
+/** last_leaf_for_name_resolutioning support. */
 struct vers_select_conds_t
 {
   vers_range_type_t type;
@@ -2344,6 +2344,9 @@ struct TABLE_LIST
   TABLE_LIST *first_leaf_for_name_resolution();
   TABLE_LIST *last_leaf_for_name_resolution();
 
+  /* System Versioning */
+  vers_select_conds_t vers_conditions;
+
   /**
      @brief
        Find the bottom in the chain of embedded table VIEWs.