max_heap_table_size是 MySQL 中的一个系统变量,它定义了使用 MEMORY 存储引擎的临时表可以使用的最大内存。MEMORY 表的大小限制在max_heap_table_size和tmp_table_size之间,这意味着一个 MEMORY 表的最大大小不能超过max_heap_table_size,否则就会出现错误。 默认情况下,max_heap_table_size的值为 16MB。随着...
max_connections =2048 max_allowed_packet =64M max_connect_errors =1000 tmp_table_size =512M max_heap_table_size =256M query_cache_size =128M tmp_table_size =256M max_heap_table_size =256M join_buffer_size =256k read_buffer_size =256k read_rnd_buffer_size =256k log_error =/usr/...
Description: The test sum_distinct-big fails in 5.5 with a wrong result if max_heap_table_size is reduced: SELECT SUM(DISTINCT id) sm FROM t2; sm 134225920 SET max_heap_table_size=16384; SELECT SUM(DISTINCT id) sm FROM t2; sm NULL I have added the regression tag since this does ...
max_heap_table_size = 2G tmp_table_size = 2G max_tmp_tables = 128 table_open_cache = 512 sort_buffer_size = 8M read_buffer_size = 8M read_rnd_buffer_size = 8M thread_cache_size = 8 query_cache_size = 32M thread_concurrency = 8 back_log = 200 max_connections = 5000 max_connec...
max_heap_table_size=96M ###***slowqueryparameters long_query_time=0.1slow_query_log=1slow_query_log_file= /usr/local/mysql/logs/slow.log ###***binlogparameters log-bin=mysql-bin binlog_cache_size=4M max_binlog_cache_size=8M
mp_table_size和max_heap_table_size设置不要过大,另外sort_buffer_size、join_buffer_size、read_buffer_size、read_rnd_buffer_size等设置也不要过大。 三 MYSQL常见的应用架构分享 1、主从复制解决方案 这是MySQL自身提供的一种高可用解决方案,数据同步方法采用的是MySQL replication技术。MySQL replication就是从...
也可參见ORD()函数。 ORD(str) 假设字符串str最左面字符是一个多字节字符,通过以格式((firstbyteASCII code)*256+(secondbyteASCII code))[*256+thirdbyteASCII code...]返回字符的ASCII代码值来返回多字节字符代码。假设最左面的字符不是一个多字节字符。返回与ASCII()函数返回的同样值。
I'm pretty sure that what you are seeing is that the command line client is picking up options from your config file and setting max_heap_table_size for you. When you try to set it from the connector, you might not be setting the current session value. ...
[11 Oct 2010 7:07] Jonas Oreland pushed to 7.0.20 and 7.1.9[12 Oct 2010 15:58] Jon Stephens Documented bugfix as follows in the NDB-7.0.20 and 7.1.9 changelogs: The MAX_ROWS option for CREATE TABLE was ignored, which meant that it was not possible to enable multi-threaded ...
max_heap_table_size = 500M # * InnoDB # # InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/. # Read the manual for more InnoDB related options. There are many! # You might want to disable InnoDB to shrink the mysqld process by circa 100MB. ...