diff options
Diffstat (limited to 'sql/sql_cache.cc')
| -rw-r--r-- | sql/sql_cache.cc | 64 |
1 files changed, 52 insertions, 12 deletions
diff --git a/sql/sql_cache.cc b/sql/sql_cache.cc index 6bc1d5204b6..7212f6996eb 100644 --- a/sql/sql_cache.cc +++ b/sql/sql_cache.cc @@ -1,4 +1,5 @@ -/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. +/* + Copyright (c) 2000, 2010, Oracle and/or its affiliates. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -467,6 +468,7 @@ static void make_base_query(String *new_query, DBUG_ASSERT(query[query_length] == 0); DBUG_ASSERT(!is_white_space(query[0])); + new_query->length(0); // Don't copy anything from old buffer if (new_query->realloc(query_length + additional_length)) { /* @@ -545,8 +547,11 @@ insert_space: } if (buffer == last_space) buffer--; // Remove the last space - *buffer= 0; + *buffer= 0; // End zero after query new_query->length((size_t) (buffer - new_query->ptr())); + + /* Copy db_length */ + memcpy(buffer+1, query_end+1, QUERY_CACHE_DB_LENGTH_SIZE); } @@ -1482,7 +1487,8 @@ def_week_frmt: %lu, in_trans: %d, autocommit: %d", /* Key is query + database + flag */ if (thd->db_length) { - memcpy((char*) (query + query_length + 1), thd->db, thd->db_length); + memcpy((char*) (query + query_length + 1 + QUERY_CACHE_DB_LENGTH_SIZE), + thd->db, thd->db_length); DBUG_PRINT("qcache", ("database: %s length: %u", thd->db, (unsigned) thd->db_length)); } @@ -1490,8 +1496,8 @@ def_week_frmt: %lu, in_trans: %d, autocommit: %d", { DBUG_PRINT("qcache", ("No active database")); } - tot_length= query_length + thd->db_length + 1 + - QUERY_CACHE_FLAGS_SIZE; + tot_length= (query_length + thd->db_length + 1 + + QUERY_CACHE_DB_LENGTH_SIZE + QUERY_CACHE_FLAGS_SIZE); /* We should only copy structure (don't use it location directly) because of alignment issue @@ -1654,7 +1660,7 @@ Query_cache::send_result_to_client(THD *thd, char *org_sql, uint query_length) Query_cache_block_table *block_table, *block_table_end; ulong tot_length; Query_cache_query_flags flags; - const char *sql, *sql_end; + const char *sql, *sql_end, *found_brace= 0; DBUG_ENTER("Query_cache::send_result_to_client"); /* @@ -1728,9 +1734,16 @@ Query_cache::send_result_to_client(THD *thd, char *org_sql, uint query_length) case '\n': case '\t': case ' ': - case '(': // To handle (select a from t1) union (select a from t1); sql++; continue; + case '(': // To handle (select a from t1) union (select a from t1); + if (!found_brace) + { + found_brace= sql; + sql++; + continue; + } + /* fall trough */ default: break; } @@ -1755,7 +1768,28 @@ Query_cache::send_result_to_client(THD *thd, char *org_sql, uint query_length) DBUG_PRINT("qcache", ("The statement has a SQL_NO_CACHE directive")); goto err; } + { + /* + We have allocated buffer space (in alloc_query) to hold the + SQL statement(s) + the current database name + a flags struct. + If the database name has changed during execution, which might + happen if there are multiple statements, we need to make + sure the new current database has a name with the same length + as the previous one. + */ + size_t db_len= uint2korr(sql_end+1); + if (thd->db_length != db_len) + { + /* + We should probably reallocate the buffer in this case, + but for now we just leave it uncached + */ + DBUG_PRINT("qcache", + ("Current database has changed since start of query")); + goto err; + } + } /* Try to obtain an exclusive lock on the query cache. If the cache is disabled or if a full cache flush is in progress, the attempt to @@ -1772,8 +1806,11 @@ Query_cache::send_result_to_client(THD *thd, char *org_sql, uint query_length) Query_cache_block *query_block; if (thd->variables.query_cache_strip_comments) { + if (found_brace) + sql= found_brace; make_base_query(&thd->base_query, sql, (size_t) (sql_end - sql), - thd->db_length + 1 + QUERY_CACHE_FLAGS_SIZE); + thd->db_length + 1 + QUERY_CACHE_DB_LENGTH_SIZE + + QUERY_CACHE_FLAGS_SIZE); sql= thd->base_query.ptr(); query_length= thd->base_query.length(); } @@ -1783,12 +1820,15 @@ Query_cache::send_result_to_client(THD *thd, char *org_sql, uint query_length) thd->base_query.set(sql, query_length, system_charset_info); } - tot_length= query_length + thd->db_length + 1 + QUERY_CACHE_FLAGS_SIZE; + tot_length= (query_length + 1 + QUERY_CACHE_DB_LENGTH_SIZE + + thd->db_length + QUERY_CACHE_FLAGS_SIZE); + if (thd->db_length) { - memcpy((char*) (sql+query_length+1), thd->db, thd->db_length); + memcpy((uchar*) sql + query_length + 1 + QUERY_CACHE_DB_LENGTH_SIZE, + thd->db, thd->db_length); DBUG_PRINT("qcache", ("database: '%s' length: %u", - thd->db, (unsigned)thd->db_length)); + thd->db, (uint) thd->db_length)); } else { @@ -1910,7 +1950,7 @@ def_week_frmt: %lu, in_trans: %d, autocommit: %d", { DBUG_PRINT("qcache", ("Temporary table detected: '%s.%s'", - table_list.db, table_list.alias)); + tmptable->s->db.str, tmptable->alias.c_ptr())); unlock(); /* We should not store result of this query because it contain |