报错场景：
处理数据相对较大6000万条的情况下，不知道为什么执行语句过程中出现了
Error： lost connection to MYSQL server during query
问题们
第一个问题：Error1175_SQL_SAFE_UPDATES
Error Code: 1175. You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. To disable safe mode, toggle the option in Preferences -> SQL Editor and reconnect. 0.016 sec
第二个问题：Error Code: . Lost connection to MySQL server during query
update userbehavior set datetime=from_unixtime(time) Error Code: . Lost connection to MySQL server during query 30.015 sec
解决方案：
Error1175问题解决方案：
*#执行语句*update userbehavior set datetime=from_unixtime(time);*#报错*14:20:08update userbehavior set datetime=from_unixtime(time)Error Code: 1175. You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column. To disable safe mode, toggle the option in Preferences -> SQL Editor and reconnect.0.016 sec*#SQL_SAFE_UPDATES的变量，此值默认为1，确保数据库更新操作的安全性。当我们批量更新数据库时，会出现更新失败的报错情况*SET SQL_SAFE_UPDATES = 0;update userbehavior set datetime=from_unixtime(time);
Error解决方案：（大名鼎鼎的error
Step1: 尝试网上方法修改服务中的参数或者重启服务；
不管用，因为不适用于运行中停止的情况
Step2: 尝试网上方法mysql workbench修改参数 Edit> Preferences> SQL editor> mysql session 改成以下参数
DBMS connection read timeout interval 600 > 0
DBMS connection timeout interval 600 > 1500
运行后仍报错，Duration/Fetch 的值没有超过600sec, 问题不在此处
Step3: 尝试网上方法> ini文件相关
1.有没有ini文件
安装数据库的时候一般会创建一个my.ini文件，没有的话可以自己手动创建，这是mysql的配置文件
一般情况下的存放位置
2.在my.ini中添加skip-name-resolve
不要搞，会报错，新报错的解决方法是#掉skip-name-resolve ； 没意义
3.修改my.ini中参数 修改完成后即可
完整的修改后的my.ini文件在此，仅供参考
# Other default tuning values# MySQL Server Instance Configuration File# ----------------------------------------------------------------------# Generated by the MySQL Server Instance Configuration Wizard### Installation Instructions# ----------------------------------------------------------------------## On Linux you can copy this file to /etc/f to set global options,# mysql-data-dir/f to set server-specific options# (@localstatedir@ for this installation) or to# ~/.f 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 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### Guidelines 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.## For advice on how to change settings please see# /doc/refman/5.7/en/server-configuration-defaults.html### 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]# pipe=# socket=MYSQLport=3306[mysql]no-beep# default-character-set=# 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.## server_type=2[mysqld]#skip-name-resolve# The next three options are mutually exclusive to SERVER_PORT below.# skip-networking# enable-named-pipe# shared-memory# shared-memory-base-name=MYSQL# The Pipe the MySQL Server will use# socket=MYSQL# The TCP/IP Port the MySQL Server will listen onport=3306# Path to installation directory. All paths are usually resolved relative to this.# basedir="C:/Program Files/MySQL/MySQL Server 5.7/"# Path to the database rootdatadir=C:/ProgramData/MySQL/MySQL Server 5.7/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=# The default storage engine that will be used when create new tables whendefault-storage-engine=INNODB# Set the SQL mode to strictsql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"# General and Slow logging.log-output=FILEgeneral-log=0general_log_file="DESKTOP-41ELTKL.log"slow-query-log=1slow_query_log_file="DESKTOP-41ELTKL-slow.log"long_query_time=10# Error Logging.log-error="DESKTOP-41ELTKL.err"# ***** Group Replication Related *****# Specifies the base name to use for binary log files. With binary logging# enabled, the server logs all statements that change data to the binary# log, which is used for backup and replication.# log-bin# ***** Group Replication Related *****# Specifies the server ID. For servers that are used in a replication topology,# you must specify a unique server ID for each replication server, in the# range from 1 to 2^32 − 1. “Unique” means that each ID must be different# from every other ID in use by any other replication source or replica.server-id=1# ***** Group Replication Related *****# Defines the algorithm used to hash the writes extracted during a transaction. If you# are using Group Replication, this variable must be set to XXHASH64 because the process# of extracting the writes from a transaction is required for conflict detection on all# group members.# transaction_write_set_extraction=0.0lower_case_table_names=1# Secure File Priv.secure-file-priv="C:/ProgramData/MySQL/MySQL Server 5.7/Uploads"# 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=800# 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_open_cache=2000# 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=382M# 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=10#*** 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# The size of the buffer that is allocated when sorting MyISAM indexes# during a REPAIR TABLE or when creating indexes with CREATE INDEX# or ALTER TABLE.myisam_sort_buffer_size=750M# 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=64M# 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=64Kread_rnd_buffer_size=256K#*** INNODB Specific options ***# innodb_data_home_dir=# 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# 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=0# 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=1M# 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=1024M# 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=50M# 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=17# The increment size (in MB) for extending the size of an auto-extend InnoDB system tablespace file when it becomes full.innodb_autoextend_increment=64M# The number of regions that the InnoDB buffer pool is divided into.# For systems with buffer pools in the multi-gigabyte range, dividing the buffer pool into separate instances can improve concurrency,# by reducing contention as different threads read and write to cached pages.innodb_buffer_pool_instances=8# Determines the number of threads that can enter InnoDB concurrently.innodb_concurrency_tickets=5000# Specifies how long in milliseconds (ms) a block inserted into the old sublist must stay there after its first access before# it can be moved to the new sublist.innodb_old_blocks_time=1000# When this variable is enabled, InnoDB updates statistics during metadata statements.innodb_stats_on_metadata=0# When innodb_file_per_table is enabled (the default in 5.6.6 and higher), InnoDB stores the data and indexes for each newly created table# in a separate .ibd file, rather than in the system tablespace.innodb_file_per_table=1# Use the following list of values: 0 for crc32, 1 for strict_crc32, 2 for innodb, 3 for strict_innodb, 4 for none, 5 for strict_none.innodb_checksum_algorithm=0# The number of outstanding connection requests MySQL can have.# This option is useful when the main MySQL thread gets many connection requests in a very short time.# It then takes some time (although very little) for the main thread to check the connection and start a new thread.# The back_log value indicates how many requests can be stacked during this short time before MySQL momentarily# stops answering new requests.# You need to increase this only if you expect a large number of connections in a short period of time.back_log=100# If this is set to a nonzero value, all tables are closed every flush_time seconds to free up resources and# synchronize unflushed data to disk.# This option is best used only on systems with minimal resources.flush_time=0# The minimum size of the buffer that is used for plain index scans, range index scans, and joins that do not use# indexes and thus perform full table scans.join_buffer_size=256K# The maximum size of one packet or any generated or intermediate string, or any parameter sent by the# mysql_stmt_send_long_data() C API function.max_allowed_packet=500M# If more than this many successive connection requests from a host are interrupted without a successful connection,# the server blocks that host from performing further connections.max_connect_errors=100# Changes the number of file descriptors available to mysqld.# You should try increasing the value of this option if mysqld gives you the error "Too many open files".open_files_limit=4161# If you see many sort_merge_passes per second in SHOW GLOBAL STATUS output, you can consider increasing the# sort_buffer_size value to speed up ORDER BY or GROUP BY operations that cannot be improved with query optimization# or improved indexing.sort_buffer_size=256K# The number of table definitions (from .frm files) that can be stored in the definition cache.# If you use a large number of tables, you can create a large table definition cache to speed up opening of tables.# The table definition cache takes less space and does not use file descriptors, unlike the normal table cache.# The minimum and default values are both 400.table_definition_cache=1400# Specify the maximum size of a row-based binary log event, in bytes.# Rows are grouped into events smaller than this size if possible. The value should be a multiple of 256.binlog_row_event_max_size=8K# If the value of this variable is greater than 0, a replica synchronizes its master.info file to disk.# (using fdatasync()) after every sync_master_info events.sync_master_info=10000# If the value of this variable is greater than 0, the MySQL server synchronizes its relay log to disk.# (using fdatasync()) after every sync_relay_log writes to the relay log.sync_relay_log=10000# If the value of this variable is greater than 0, a replica synchronizes its relay-log.info file to disk.# (using fdatasync()) after every sync_relay_log_info transactions.sync_relay_log_info=10000# Load mysql plugins at start."plugin_x ; plugin_y".# plugin_load# The TCP/IP Port the MySQL Server X Protocol will listen on.# loose_mysqlx_port=33060
