帮我写一个连接到远程pg库然后备份表的shell脚本

创建一个连接到远程PostgreSQL数据库并备份特定表的Shell脚本通常涉及使用`psql`命令行工具。以下是一个基础的示例，假设你知道数据库的详细信息，如主机名、端口、用户名、密码以及要备份的表名：

#!/bin/bash

# 数据库连接信息
DB_HOST="your_host"
DB_PORT=5432
DB_NAME="your_database"
DB_USER="your_username"
DB_PASS="your_password"

# 要备份的表名
TABLE_NAME="your_table_name"

# 创建临时文件名用于存储备份
BACKUP_FILE="/tmp/backup_$(date +%Y%m%d%H%M%S).sql"

# 使用psql执行备份命令
echo "Creating backup..."
pg_dump -h $DB_HOST -p $DB_PORT -U $DB_USER -d $DB_NAME --table $TABLE_NAME > $BACKUP_FILE
if [ $? -eq 0 ]; then
    echo "Backup completed successfully."
else
    echo "Backup failed."
fi

# 可选：将备份文件压缩并删除
echo "Compressing and removing the temporary file..."
gzip $BACKUP_FILE
rm $BACKUP_FILE

# 确保备份目录存在
mkdir -p /path/to/backup/directory
mv *.gz /path/to/backup/directory/

# 提供反馈和询问是否需要清理旧备份
echo "Backup is available at /path/to/backup/directory."
read -p "Do you want to clean up old backups? (y/n) " clean_up
if [[ "$clean_up" =~ ^[Yy]$ ]]; then
    find /path/to/backup/directory -mtime +7 -type f -delete
    echo "Old backups have been cleaned."
fi

# 清理日志
echo "Script finished."