我在 RHEL 中为 2 个节点设置了 Master Master 复制设置。一个服务器充当另一个服务器（也是 Master 和 Slave）的 Master 和 slave 假设 A 服务器和 B 服务器
我在 B 服务器上启用了 log_slave_updates，以便从主服务器（服务器 A）接收的所有语句都应该记录到服务器 B 的二进制日志中。
我期待复制，会失败，因为：
1. Created a Table on Server A.
2. It get replicated to Server B.
现在，从属 B 的二进制日志将转到服务器 A，这应该会中断复制，提示“表已存在”。但它没有
这里的逻辑是什么？
编辑部分：
我在 Linux 服务器中有一个主服务器复制设置。
主配置详细信息：
MySQL version is 5.1 and replication mode is MIXED type.
从站配置详细信息：
MySQL version is 5.6
如果我插入单个记录，那么它将被复制到从属。
当我运行脚本在 master 插入数千条记录时，它不会被复制。
当我看到二进制日志文件的大小时，它是 908 MB，当我看到中继日志文件的大小时，它是 560 KB。
二进制日志文件的大小是否重要？
或者这可能是什么原因。
以下是主cnf详细信息：
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
bind-address = #master IP# ( not showing here )
port=3306
wait_timeout=90
net_read_timeout=90
connect_timeout=90
max_connections=100
lower_case_table_names=1
log-bin=mysql-bin
binlog_format=MIXED
server-id=1
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
如果我一个一个地执行这些查询，除了第一个之外都失败：
查询1：
flush table tablename1 with read lock;
作品
查询2：
flush table tablename2 with read lock;
错误：无法执行给定的命令，因为您有活动的锁定表 mysql
如果我按以下方式执行，它将起作用：
询问：
flush table tablename1,tablename2 with read lock;
里面发生了什么？
我在一台服务器 A（从 S）上有 1 个 mysql 5.6 实例
1 Mysql安装在服务器B（Master M1）
1 MySql 安装在服务器 C ( Master M2 )
At Slave end :
I have created one more instance by creating one more my.conf file from existing my.cnf in Slave and placed it in "C:\Program Files (x86)\MySQL\MySQL Server 5.6\my.conf" which looks like this :
# MySQL Server Instance Configuration File
# ----------------------------------------------------------------------
# Generated by the MySQL Server Instance Configuration Wizard
#
#
# Installation Instructions
# ----------------------------------------------------------------------
#
# On Linux you can copy this file to /etc/my.cnf to set global options,
# mysql-data-dir/my.cnf to set server-specific options
# (@localstatedir@ for this installation) or to
# ~/.my.cnf to set user-specific options.
#
# On Windows you should keep this file in the installation directory
# of your server (e.g. C:\Program Files\MySQL\MySQL Server X.Y). To
# make sure the server reads the config file use the startup option
# "--defaults-file".
#
# To run run the server from the command line, execute this in a
# command line shell, e.g.
# mysqld --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
#
# To install the server as a Windows service manually, execute this in a
# command line shell, e.g.
# mysqld --install MySQLXY --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
#
# And then execute this in a command line shell to start the server, e.g.
# net start MySQLXY
#
#
# Guildlines for editing this file
# ----------------------------------------------------------------------
#
# In this file, you can use all long options that the program supports.
# If you want to know the options a program supports, start the program
# with the "--help" option.
#
# More detailed information about the individual options can also be
# found in the manual.
#
#
# CLIENT SECTION
# ----------------------------------------------------------------------
#
# The following options will be read by MySQL client applications.
# Note that only client applications shipped by MySQL are guaranteed
# to read this section. If you want your own MySQL client program to
# honor these values, you need to specify it as an option during the
# MySQL client library initialization.
#
[client]
port=3306
#ssl-ca=ca.pem
#ssl-cert=client-cert.pem
#ssl-key=client-key.pem
[mysql]
default-character-set=utf8
# SERVER SECTION
# ----------------------------------------------------------------------
#
# The following options will be read by the MySQL Server. Make sure that
# you have installed the server correctly (see above) so it reads this
# file.
#
[mysqld]
server-id=1
log-bin=mysql-bin
binlog_format=ROW
# The TCP/IP Port the MySQL Server will listen on
port=3306
innodb_file_per_table = 1
innodb_file_format = barracuda
max_allowed_packet = 256M
innodb_lock_wait_timeout=120
transaction-isolation = READ-COMMITTED
interactive_timeout=300
wait_timeout=300
#Path to installation directory. All paths are usually resolved relative to this.
basedir="C:/Program Files (x86)/MySQL/MySQL Server 5.6/"
#Path to the database root
datadir="C:/ProgramData/MySQL/MySQL Server 5.6/Data/"
# The default character set that will be used when a new schema or table is
# created and no character set is defined
character-set-server=utf8
# The default storage engine that will be used when create new tables when
default-storage-engine=INNODB
# The default storage engine that will be used for temporary tables
default-tmp-storage-engine=INNODB
# Set the SQL mode to strict
sql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
# The maximum amount of concurrent sessions the MySQL server will
# allow. One of these connections will be reserved for a user with
# SUPER privileges to allow the administrator to login even if the
# connection limit has been reached.
max_connections=1510
# Query cache is used to cache SELECT results and later return them
# without actual executing the same query once again. Having the query
# cache enabled may result in significant speed improvements, if your
# have a lot of identical queries and rarely changing tables. See the
# "Qcache_lowmem_prunes" status variable to check if the current value
# is high enough for your load.
# Note: In case your tables change very often or if your queries are
# textually different every time, the query cache may result in a
# slowdown instead of a performance improvement.
query_cache_size=164M
# The number of open tables for all threads. Increasing this value
# increases the number of file descriptors that mysqld requires.
# Therefore you have to make sure to set the amount of open files
# allowed to at least 4096 in the variable "open-files-limit" in
# section [mysqld_safe]
table_cache=3020
# Maximum size for internal (in-memory) temporary tables. If a table
# grows larger than this value, it is automatically converted to disk
# based table This limitation is for a single table. There can be many
# of them.
tmp_table_size=30M
# How many threads we should keep in a cache for reuse. When a client
# disconnects, the client's threads are put in the cache if there aren't
# more than thread_cache_size threads from before. This greatly reduces
# the amount of thread creations needed if you have a lot of new
# connections. (Normally this doesn't give a notable performance
# improvement if you have a good thread implementation.)
thread_cache_size=64
#*** MyISAM Specific options
# The maximum size of the temporary file MySQL is allowed to use while
# recreating the index (during REPAIR, ALTER TABLE or LOAD DATA INFILE.
# If the file-size would be bigger than this, the index will be created
# through the key cache (which is slower).
myisam_max_sort_file_size=100G
# If the temporary file used for fast index creation would be bigger
# than using the key cache by the amount specified here, then prefer the
# key cache method. This is mainly used to force long character keys in
# large tables to use the slower key cache method to create the index.
myisam_sort_buffer_size=30M
# Size of the Key Buffer, used to cache index blocks for MyISAM tables.
# Do not set it larger than 30% of your available memory, as some memory
# is also required by the OS to cache rows. Even if you're not using
# MyISAM tables, you should still set it to 8-64M as it will also be
# used for internal temporary disk tables.
key_buffer_size=252M
# Size of the buffer used for doing full table scans of MyISAM tables.
# Allocated per thread, if a full scan is needed.
read_buffer_size=64K
read_rnd_buffer_size=256K
# This buffer is allocated when MySQL needs to rebuild the index in
# REPAIR, OPTIMZE, ALTER table statements as well as in LOAD DATA INFILE
# into an empty table. It is allocated per thread so be careful with
# large settings.
sort_buffer_size=256K
#*** INNODB Specific options ***
# Use this option if you have a MySQL server with InnoDB support enabled
# but you do not plan to use it. This will save memory and disk space
# and speed up some things.
#skip-innodb
# Additional memory pool that is used by InnoDB to store metadata
# information. If InnoDB requires more memory for this purpose it will
# start to allocate it from the OS. As this is fast enough on most
# recent operating systems, you normally do not need to change this
# value. SHOW INNODB STATUS will display the current amount used.
innodb_additional_mem_pool_size=11M
# If set to 1, InnoDB will flush (fsync) the transaction logs to the
# disk at each commit, which offers full ACID behavior. If you are
# willing to compromise this safety, and you are running small
# transactions, you may set this to 0 or 2 to reduce disk I/O to the
# logs. Value 0 means that the log is only written to the log file and
# the log file flushed to disk approximately once per second. Value 2
# means the log is written to the log file at each commit, but the log
# file is only flushed to disk approximately once per second.
innodb_flush_log_at_trx_commit=1
# The size of the buffer InnoDB uses for buffering log data. As soon as
# it is full, InnoDB will have to flush it to disk. As it is flushed
# once per second anyway, it does not make sense to have it very large
# (even with long transactions).
innodb_log_buffer_size=5M
# InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and
# row data. The bigger you set this the less disk I/O is needed to
# access data in tables. On a dedicated database server you may set this
# parameter up to 80% of the machine physical memory size. Do not set it
# too large, though, because competition of the physical memory may
# cause paging in the operating system. Note that on 32bit systems you
# might be limited to 2-3.5G of user level memory per process, so do not
# set it too high.
innodb_buffer_pool_size=489M
# Size of each log file in a log group. You should set the combined size
# of log files to about 25%-100% of your buffer pool size to avoid
# unneeded buffer pool flush activity on log file overwrite. However,
# note that a larger logfile size will increase the time needed for the
# recovery process.
innodb_log_file_size=98M
# Number of threads allowed inside the InnoDB kernel. The optimal value
# depends highly on the application, hardware as well as the OS
# scheduler properties. A too high value may lead to thread thrashing.
innodb_thread_concurrency=8
[mysqld1]
basedir ="C:\Program Files (x86)\MySQL\MySQL Server 5.6"
port = 3307
enable-named-pipe
socket = mypipe1
[mysqld2]
basedir ="C:\Program Files (x86)\MySQL\MySQL Server 5.6"
port = 3308
enable-named-pipe
socket = mypipe2
现在我想将 M1 和 M2 都复制到 slave s。我应该怎么做？
我需要在同一台服务器上安装多个 Mysql 实例。我浏览过很多链接，但我在这里感到困惑：
What i have : MySQL 5.6 is already installed on my windows server A.
Installed at : "C:\Program Files (x86)\MySQL\MySQL_Server_5.6\"
Problem : For multiple instances , do i need to download and install new mysql(either same or higher version) on server A ?
OR
should i just copy existing my.conf file in new folder and then change its port number and then done.
我自己的分析继续全新安装，但请确认。
我有的 ：
Test数据库有一个名为activity列的表id和class我需要的 ：
test.activity将表复制到test2数据库的条件是Test.activity.class = 'B'.我知道如何在不同的服务器上进行复制。但不适用于不同数据库中的同一服务器。我已经检查了这个链接，但它没有提供足够的信息。
有这个查询产生以下输出：
select sec.site,sec.Name,sec.Freq from
( select Name from sec group by name having count(Freq) > 3)as dt
inner join sec on dt.Name = sec.Name
where sec.Freq like '%MUF2900%' ;
site Name Freq
S003 sct003a MUF2900_26
S003 sct003a MUF2900_26
S003 sct003a MUF2900_26
S034 sct034a MUF2900_26
S034 sct034a MUF2900_26
S034 sct034a MUF2900_26
现在我必须根据上述查询的输出更新我的另一个表名测试。表测试当前包含以下记录（更新前）：
site cell ID
S003 09M00011 1019581
S003 09M00012 1019582
S003 09M00013 1019583
S003 29M00011 1019581
S003 29M00012 1019582
S003 29M00013 1019583
S034 09M00011 1016581
S034 09M00011 1016582
S034 09M00011 1016583
now for site S003 , ID for for cell starting from 09 and 29 are same ,so i need to update the ID for 29 i.e the unit place of ID should be incremented by 10 , like following..
必需的 ：
Site cell ID
S003 09M00011 1019581
S003 09M00012 1019582
S003 09M00013 1019583
S003 29M00011 10195811
S003 29M00012 10195812
S003 29M00013 10195813
S034 09M00011 1016581
S034 09M00011 1016582
S034 09M00011 1016583
我有很多这样的记录。
注意：S034 没有从 29 开始的单元格，所以它的 ID 不需要更新。
我尝试过的和我感到困惑的地方是：
update Test set ID = (how to do this ??)
where Test.site = (select sec.site,sec.Name,sec.Freq from
( select Name from sec group by Name having count(Freq) > 3)as dt
inner join sec on dt.Name = Sec.Name
where sec.Freq like '%MUF2900%') where cell like '29M%';
我应该怎么做。我需要为此制作光标吗？？
虽然，我努力使问题易于理解，但我仍然不知道出了什么问题。不管怎样，我正在努力使它更紧凑
我现在只有下表：
在列号中，JU 表示 Junior，SU 表示 Senior
name number fin
------------------------------------
paul JU00011 100401
paul JU00012 100402
paul JU00012 100403
maul JU00021 100641
maul JU00022 100642
paul SU00012 100401
paul SU00012 100402
paul SU00012 100403
Now in this table , fin for paul are same ( for junior ans senior ).
i need to make an update in this table
for example :If paul is coming under two numbers (i.e JU and SU) and have same fin number,
so i want to update fin , when 2 fin are same and belongs to same name and is coming under Junior category and Senior Category
Final Result :
name number fin
------------------------------------
paul JU00011 100401
paul JU00012 100402
paul JU00012 100403
maul JU00021 100641
maul JU00022 100642
paul SU00012 1004011
paul SU00012 1004012
paul SU00012 1004013
Such type of records are more.
我有一个表 T1 列：
Name State time
mon 1 2014-01-09 11:23:00
tue 0 2014-01-07 14:40:00
wed 2 2014-01-08 09:23:00
thu 0 2014-01-09 12:23:00
现在我想安排一个事件或开发一个触发器（如果可能的话），如果任何状态是 0/2 并且它的时间比当前时间超过 24 小时，那么它应该更新为 1。
例如在上表中，Tue 的状态为 0，时间超过 24 小时，因此 state 应更新为 1，同样适用于 wed，但不适用于 thu。
我经历了很多问题，例如：
https://stackoverflow.com/questions/17387802/how-to-auto-update-mysql-after-timestamp-field-expierd
https://stackoverflow.com/questions/12421756/how-to-update-table-after-a-certain-time-interval
但我还不明白，如何解决我的问题
mysql / oracle 中是否有任何实用程序/功能可以防止我错误地发出一些删除/更新命令，必须在 command_line* （如果可能在 ubuntu 中）提示一条消息，询问是否“您确定运行此命令”，如果是，则删除/update 命令会执行吗？
我已经用谷歌搜索了这个，但没有为此提供具体的解决方案。我也尝试了 SOURCE，但这并不是我想要的。
有人对此有任何想法吗？
如果我要对 > 100 000 条记录执行更新命令，应该会出现一个提示，询问“你真的要运行吗？”，就像在 Unix 中，如果我们使用 rm 文件名，它会询问你是否确定要删除?
我有一个包含以下 5 列的表格。时间戳是时间日期相关列的数据类型：
Region event_time start_time mid_time end_time
India 2013-11-03 13:00:00
America
Holland
Switzerland
我有来自上列数据以特定时间间隔出现的来源..现在插入时我需要添加时间。
对于前。如果在 csv 文件中我有 2013-11-03 13:00:00 的 event_time，那么对于印度时间在插入之前添加 5:30（由于格林威治标准时间）..最终插入的值应该是 2013-11-03 18 :30:00 ..同样适用于其余地区和日期时间列..我应该怎么做...此外夏令时将包括其他有此功能的地区
我尝试了 adddate 和 addtime 函数..但这不起作用...我尝试在插入后进行更新，但这不是我想要的解决方案...有什么帮助吗？？
我在一个表中有两列：STOP和START，类型为varchar。
我想在两列之间有所区别，我正在使用：
SELECT DATEDIFF(stop, start) AS difference from T1;
null由于不同的数据类型，它给了我。
为了测试，我还尝试了：
SELECT STR_TO_DATE('5/16/2011 20:14 PM', '%c %e %Y %H:%i:%s');
它也在给予null。
我该怎么办？我有n不同格式的数据和时间。
我有一个包含这些列的表，这些值以 n 分钟的固定间隔从 csv 文件进入这些表（通过 cron load infile 命令）：
ID (PK) status first last value
1 Q 12 15 low
2 Q 12 15 low
3 O 12 15 High
现在每当下一个数据到来时，它应该首先检查表中是否存在 ID，如果存在则更新该 ID 的相应字段，如果有新 ID 到来，它只需插入数据。
为此，我创建了一个程序：
create procedure test.testproc (IN no int , IN status varchar(10))
begin if exists (select id from test.testproc where id = no)
then
update baseline set status=status where id=no;
else insert into tname(id,status) value(no,status);
end if;
end$$
现在我想知道的是：
我应该为此创建两个表，即一个是临时表和一个主表吗？** 我 100% 困惑在这里我应该做什么
我应该如何自动化所有这些 ie 数据来自 csv 文件，然后我的加载 infile 脚本运行，然后我的上述过程应该执行并检查如果 ID 已经存在它会简单地更新否则它会插入。
或者，如果您有任何其他过程，请告诉
我有 2 个表，TA并且TB：
TA
--------
id name
1 a
2 b
3 c
4 d
5 e
6 f
TB
--------
id p_id name
1 1 a
2 1 b
3 1 c
4 2 a
5 2 b
6 2 d
我需要：如果p_id = 1那么：
id name match
1 a 1
2 b 1
3 c 1
4 d 0
5 e 0
6 f 0
如果p_id = 2那么：
id name match
1 a 1
2 b 1
3 c 0
4 d 1
5 e 0
6 f 0
我在这里很困惑，我创建了一个表并有 2 列 id 和 name。
现在 id 是主键，而不是 null 和自动递增。
假设我开火：insert into table (name) values('test');
这会给我：
1 | test
现在如果我开火：alter table table_name auto_increment = 5;
这将在下一次插入时用 5 填充 id。
现在，如果我删除 id =5 的值并再次重新插入：insert into table (name) values ('test2');
它给了我：
6 | test2
为什么它不再给我5？
另外，我们不可能在 MySql 中将现有的 auto_increment 值重置为所需的值吗？
我有 2 张桌子：
表格1
父（varchar）子（varchar）
表2
C1(varchar) PC (varchar)
样本数据：
要求 - 我需要 Table2.C1 列的 Table2.PC = Table1.Child 值，但子值必须与 Table1.Parent 的值不同。
我在mysql中使用以下查询：
select distinct(C1),Child,PC
from Table2 inner join Table1
on Table2.PC=Table1.Child
where Table1.Child not in (select Parent from Table1);
它给出了空集，但 Child 中的值与 PC 中的值相同，但 Parent 中没有。
我哪里错了？
我有一个表 T1，它有两列empname，department
每个 emp 必须在 37 部门，但也有一些员工在 37 部门以下。
我需要找到不在所有 37 个部门中的 emp 的名称。
我正在使用查询：
select empname from T1 having count (department) < 37;
但它没有给我想要的输出。
我有一个表，其中有一个名为state(int(2))and的列modify_time（time_stamp更新当前时间戳）。
0我有一个更新触发器，它根据某些条件将状态列的值更改为。
我想将statecolumn的值设置为124 小时后modify_time，如果它仍然是0。
我尝试了以下方法进行测试：
CREATE EVENT myevent1
ON SCHEDULE AT current_timestamp + interval 1 minute
DO UPDATE test.mytabletable SET state = 0;
这并没有做任何事情。有没有替代方法？
我有这个触发器：
delimiter $$
create trigger tr
after update on t1
for each row
begin
if new.col1 !=old.col1
then update t2 set col2 =1 where t2.col3=t1.col3;
end if;
end
$$
此触发器在col1' 的值从 0 更改为 1 时起作用，但当其从 null 更改为 1 时，触发器不会对t2.
我只是想知道为什么会这样。我知道 null 是不同的，但我只是在比较值。
我已经解决了我的问题new.col1 =1。
我有一个触发器，它在插入行后更新不同表中的列：
mysql>delimiter $$
mysql> create trigger status
after insert on table2
FOR EACH ROW
BEGIN update
table1 inner join table2
ON table1.id=table2.id
set table1.state=0 ;
现在我想table1.state=1在删除相同的值时重置。这可能吗？