默认情况下，MySQL镜像创建的Docker容器启动时只是一个空的数据库实例，为了简化Docker部署，需要在Docker创建MySQL容器时：
也就是说容器启动后数据库就可用了。
这就需要容器启动时能自动执行sql脚本。
在MySQL官方镜像中提供了容器启动时自动执行/docker-entrypoint-initdb.d文件夹下的脚本的功能(包括shell脚本和sql脚本) 。docker-entrypoint.sh中下面这段代码就是干这事儿的。
# usage: process_init_file FILENAME MYSQLCOMMAND... # ie: process_init_file foo.sh mysql -uroot # (process a single initializer file, based on its extension. we define this # function here, so that initializer scripts (*.sh) can use the same logic, # potentially recursively, or override the logic used in subsequent calls) process_init_file() { local f="$1"; shift local mysql=( "$@" ) case "$f" in *.sh) echo "$0: running $f"; . "$f" ;; *.sql) echo "$0: running $f"; "${mysql[@]}" < "$f"; echo ;; *.sql.gz) echo "$0: running $f"; gunzip -c "$f" | "${mysql[@]}"; echo ;; *) echo "$0: ignoring $f" ;; esac echo } echo ls /docker-entrypoint-initdb.d/ > /dev/null for f in /docker-entrypoint-initdb.d/*; do process_init_file "$f" "${mysql[@]}" done
也就是说只要把初始化脚本放到/docker-entrypoint-initdb.d/文件夹MySQL容器在启动的时候就会执行这些初始化脚本。