Bug#18888 Trying to overwrite sql/lex_hash.h during build

 - As a sideeffect of the patch to generate lex_hash.h only once
on the machine where the source dist was produced, a problem
was found when compiling a mysqld without partition support - it 
would crash when looking up the lex symbols due to mismatch between
lex.h and the generated lex_hash.h

 - Remove the ifdef for partition in lex.h 
 - Fix minor problem with"EXPLAIN PARTITION" when not compiled with
   partition(existed also without the above patch)
 - Add test case that will be run when we don't have partition
   support compiled into mysqld
 - Return error ER_FEATURE_DISABLED if user tries to use PARTITION
   when there is no support for it.

mysql-test/r/not_partition.require

+Variable_name	Value
+have_partitioning	NO

mysql-test/r/not_partition.result

+CREATE TABLE t1 (
+firstname VARCHAR(25) NOT NULL,
+lastname VARCHAR(25) NOT NULL,
+username VARCHAR(16) NOT NULL,
+email VARCHAR(35),
+joined DATE NOT NULL
+)
+PARTITION BY KEY(joined)
+PARTITIONS 6;
+ERROR HY000: The 'partitioning' feature is disabled; you need MySQL built with '--with-partition' to have it working
+ALTER TABLE t1 PARTITION BY KEY(joined) PARTITIONS 2;
+ERROR HY000: The 'partitioning' feature is disabled; you need MySQL built with '--with-partition' to have it working
+drop table t1;
+ERROR 42S02: Unknown table 't1'
+CREATE TABLE t1 (
+firstname VARCHAR(25) NOT NULL,
+lastname VARCHAR(25) NOT NULL,
+username VARCHAR(16) NOT NULL,
+email VARCHAR(35),
+joined DATE NOT NULL
+)
+PARTITION BY RANGE( YEAR(joined) ) (
+PARTITION p0 VALUES LESS THAN (1960),
+PARTITION p1 VALUES LESS THAN (1970),
+PARTITION p2 VALUES LESS THAN (1980),
+PARTITION p3 VALUES LESS THAN (1990),
+PARTITION p4 VALUES LESS THAN MAXVALUE
+);
+ERROR HY000: The 'partitioning' feature is disabled; you need MySQL built with '--with-partition' to have it working
+drop table t1;
+ERROR 42S02: Unknown table 't1'
+CREATE TABLE t1 (id INT, purchased DATE)
+PARTITION BY RANGE( YEAR(purchased) )
+SUBPARTITION BY HASH( TO_DAYS(purchased) )
+SUBPARTITIONS 2 (
+PARTITION p0 VALUES LESS THAN (1990),
+PARTITION p1 VALUES LESS THAN (2000),
+PARTITION p2 VALUES LESS THAN MAXVALUE
+);
+ERROR HY000: The 'partitioning' feature is disabled; you need MySQL built with '--with-partition' to have it working
+drop table t1;
+ERROR 42S02: Unknown table 't1'
+create table t1 (a varchar(10) charset latin1 collate latin1_bin);
+insert into t1 values (''),(' '),('a'),('a '),('a  ');
+explain partitions select * from t1 where a='a ' OR a='a';
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	5	Using where
+drop table t1;

mysql-test/t/not_partition.test

+--disable_abort_on_error
+# Run this tets only when mysqld don't has partitioning
+# the statements are not expected to work, just check that we
+# can't crash the server
+-- require r/not_partition.require
+disable_query_log;
+show variables like "have_partitioning";
+enable_query_log;
+
+
+--error ER_FEATURE_DISABLED
+CREATE TABLE t1 (
+    firstname VARCHAR(25) NOT NULL,
+    lastname VARCHAR(25) NOT NULL,
+    username VARCHAR(16) NOT NULL,
+    email VARCHAR(35),
+    joined DATE NOT NULL
+)
+PARTITION BY KEY(joined)
+PARTITIONS 6;
+
+--error ER_FEATURE_DISABLED
+ALTER TABLE t1 PARTITION BY KEY(joined) PARTITIONS 2;
+
+--error ER_BAD_TABLE_ERROR
+drop table t1;
+
+--error ER_FEATURE_DISABLED
+CREATE TABLE t1 (
+    firstname VARCHAR(25) NOT NULL,
+    lastname VARCHAR(25) NOT NULL,
+    username VARCHAR(16) NOT NULL,
+    email VARCHAR(35),
+    joined DATE NOT NULL
+)
+PARTITION BY RANGE( YEAR(joined) ) (
+    PARTITION p0 VALUES LESS THAN (1960),
+    PARTITION p1 VALUES LESS THAN (1970),
+    PARTITION p2 VALUES LESS THAN (1980),
+    PARTITION p3 VALUES LESS THAN (1990),
+    PARTITION p4 VALUES LESS THAN MAXVALUE
+);
+--error ER_BAD_TABLE_ERROR
+drop table t1;
+
+--error ER_FEATURE_DISABLED
+CREATE TABLE t1 (id INT, purchased DATE)
+    PARTITION BY RANGE( YEAR(purchased) )
+    SUBPARTITION BY HASH( TO_DAYS(purchased) )
+    SUBPARTITIONS 2 (
+        PARTITION p0 VALUES LESS THAN (1990),
+        PARTITION p1 VALUES LESS THAN (2000),
+        PARTITION p2 VALUES LESS THAN MAXVALUE
+    );
+--error ER_BAD_TABLE_ERROR
+drop table t1;
+
+# Create a table without partitions to test "EXPLAIN PARTITIONS"
+create table t1 (a varchar(10) charset latin1 collate latin1_bin);
+insert into t1 values (''),(' '),('a'),('a '),('a  ');
+explain partitions select * from t1 where a='a ' OR a='a';
+drop table t1;

sql/lex.h

@@ -45,6 +45,10 @@ SYM_GROUP sym_group_rtree= {"RTree keys", "HAVE_RTREE_KEYS"};
   Symbols are broken into separated arrays to allow field names with
   same name as functions.
   These are kept sorted for human lookup (the symbols are hashed).
+
+  NOTE! The symbol tables should be the same regardless of what features
+  are compiled into the server. Don't add ifdef'ed symbols to the
+  lists
 */
 
 static SYMBOL symbols[] = {
@@ -383,11 +387,9 @@ static SYMBOL symbols[] = {
   { "PACK_KEYS",	SYM(PACK_KEYS_SYM)},
   { "PARSER",           SYM(PARSER_SYM)},
   { "PARTIAL",		SYM(PARTIAL)},
-#ifdef WITH_PARTITION_STORAGE_ENGINE
   { "PARTITION",        SYM(PARTITION_SYM)},
   { "PARTITIONING",     SYM(PARTITIONING_SYM)},
   { "PARTITIONS",       SYM(PARTITIONS_SYM)},
-#endif
   { "PASSWORD",		SYM(PASSWORD)},
   { "PHASE",            SYM(PHASE_SYM)},
   { "PLUGIN",           SYM(PLUGIN_SYM)},

sql/sql_class.cc

@@ -859,7 +859,6 @@ int THD::send_explain_fields(select_result *result)
   field_list.push_back(new Item_empty_string("select_type", 19, cs));
   field_list.push_back(item= new Item_empty_string("table", NAME_LEN, cs));
   item->maybe_null= 1;
-#ifdef WITH_PARTITION_STORAGE_ENGINE
   if (lex->describe & DESCRIBE_PARTITIONS)
   {
     /* Maximum length of string that make_used_partitions_str() can produce */
@@ -868,7 +867,6 @@ int THD::send_explain_fields(select_result *result)
     field_list.push_back(item);
     item->maybe_null= 1;
   }
-#endif
   field_list.push_back(item= new Item_empty_string("type", 10, cs));
   item->maybe_null= 1;
   field_list.push_back(item=new Item_empty_string("possible_keys",

sql/sql_select.cc

@@ -2200,7 +2200,7 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables, COND *conds,
       continue;
     }
 #ifdef WITH_PARTITION_STORAGE_ENGINE
-    bool no_partitions_used= table->no_partitions_used;
+    const bool no_partitions_used= table->no_partitions_used;
 #else
     const bool no_partitions_used= FALSE;
 #endif

sql/sql_yacc.yy

@@ -3225,6 +3225,7 @@ opt_partitioning:
 partitioning:
         PARTITION_SYM
         {
+#ifdef WITH_PARTITION_STORAGE_ENGINE
           LEX *lex= Lex;
           lex->part_info= new partition_info();
           if (!lex->part_info)
@@ -3236,6 +3237,12 @@ partitioning:
           {
             lex->alter_info.flags|= ALTER_PARTITION;
           }
+#else
+          my_error(ER_FEATURE_DISABLED, MYF(0),
+       	           "partitioning", "--with-partition");
+          YYABORT;
+#endif
+
         }
         partition
         ;