发布于 2015-10-01 00:03:00 | 142 次阅读 | 评论: 0 | 来源: 网友投递
Mysql关系型数据库管理系统
MySQL是一个开放源码的小型关联式数据库管理系统，开发者为瑞典MySQL AB公司。MySQL被广泛地应用在Internet上的中小型网站中。由于其体积小、速度快、总体拥有成本低，尤其是开放源码这一特点，许多中小型网站为了降低网站总体拥有成本而选择了MySQL作为网站数据库。
MySQL 5.6.27 发布，暂未放出发行说明，现已提供下载：
http://dev.mysql.com/downloads/mysql/
同时发布了 MySQL 5.5.46 版本，此版本更新 yaSSL 到 2.3.8/2.3.7d，其他主要是 bug 修复：
InnoDB: A data corruption occurred on ARM64. GCC builtins did not issue the correct fences when setting or unsetting the lock word. (Bug #21102971, Bug #76135)
InnoDB: In READ COMMITTED mode, a REPLACE operation on a unique secondary index resulted in a constraint violation. Thanks to Alexey Kopytov for the patch. (Bug #21025880, Bug #76927)
InnoDB: The IBUF_BITMAP_FREE bit indicated that there was more free space in the leaf page than was actually available. (Bug #20796566)
InnoDB: Setting lower_case_table_names=0 on a case-insensitive file system could result in a hang condition when running an INSERT INTO ... SELECT ... FROM operation with the wrong tbl_nametbl_name letter case. An error message is now printed and the server exits when attempting to start the server with --lower_case_table_names=0 on a case-insensitive file system. (Bug #20198490, Bug #75185)
Partitioning: CREATE TABLE statements that used an invalid function in a subpartitioning expression did not always fail gracefully as expected. (Bug #20310212)
Partitioning: ALTER TABLE when executed from a stored procedure did not always work correctly with tables partitioned by RANGE. (Bug #16613004)
Certain subqueries as arguments to PROCEDUREANALYSE() could cause a server exit. (Bug #21350175)
mysql_ssl_rsa_setup could create an unwanted .rnd file in the data directory. (The file is actually created by openssl, which mysql_ssl_ras_setup invokes. mysql_ssl_rsa_setup now cleans up the file.) (Bug #21335818)
An assertion could be raised due to incorrect error handling if a SELECT ... FOR UPDATE subquery resulted in deadlock and caused a rollback. (Bug #21096444)
Servers linked against yaSSL and compiled with GCC 4.8.2 could fail to respond correctly to connection attempts until several seconds after startup. (Bug #21025377)
For tables with subpartitions, the server could exit due to incorrect error handling during partition pruning if the partition could be identified but not the subpartition. (Bug #20909518)
DELETE could check privileges for the wrong database when table aliases were used. (Bug #20777016)
Within a trigger, use of a cursor that accessed OLD or NEW values from a row could cause a server exit. (Bug #20760261)
MySQL sometimes produced no warning when it was unable to interpret a character in a given character set. (Bug #20238729)
For MySQL distributions linked against yaSSL, a corrupt client key file could cause clients to exit. (Bug #20168526)
Execution of certain BINLOG statements while temporary tables were open by HANDLER statements could cause a server exit. (Bug #19894987, Bug #20449914)
On Windows, setting query_cache_min_res_unit to too large a value could result in a value of 0 and a subsequent server exit. (Bug #18487951)
RPM installation scripts if configuration files contained multiple datadir lines. Now the last datadir line is used. (Bug #77878, Bug #21527467)
For wait events, the Performance Schema uses the CYCLE timer by default, but failed to fall back to a different timer if CYCLE was unavailable. (Bug #77577, Bug #21374104)
Updating VARCHAR and TEXT columns in the same UPDATE statement could produce incorrect results. When a VARCHARcolumn was assigned to a TEXT column and the VARCHAR column was then set to a different value, the TEXT column's result contained the VARCHAR column's new value. (Bug #77135, Bug #21143080)
mysqladmin -u root -p could exit with a segmentation fault. (Bug #76538, Bug #20802751)
mysqlimport --use-threads did not actually use multiple threads. (Bug #76480, Bug #20772273)
View creation from a UNION failed with a duplicate-column error if a SELECT statement in the UNION other than the first used the same column name multiple times. (Bug #74539, Bug #19886430)
Empty XML elements having the form <element/> were not handled correctly by the LOAD XML statement. (Bug #67542, Bug #16171518)
更多内容请看更新日志。