to_utc_timestamp

to_utc_timestamp函数是一种用于将本地时区时间转换为协调世界时（UTC）时间的SQL函数。协调世界时是一种标准时间，用作全球统一的时间参考。to_utc_timestamp函数通常用于处理不同时区之间的时间转换问题。

当我们在处理包含时区信息的时间数据时，有时需要将其转换为UTC时间，以便进行一致性比较或计算。to_utc_timestamp函数可以帮助我们实现这一转换。

函数的使用方式很简单。我们可以将本地时区时间作为参数传递给to_utc_timestamp函数，函数会将其转换为相应的UTC时间并返回。例如，如果本地时区时间是2022-01-01 12:00:00，且本地时区为东八区，那么调用to_utc_timestamp函数后返回的UTC时间为2022-01-01 04:00:00。

需要注意的是，to_utc_timestamp函数是基于本地系统的时区设置进行转换的。因此，在使用该函数时，要确保系统的时区设置是正确的，以避免转换出现错误。

综上所述，to_utc_timestamp函数是一种用于将本地时区时间转换为协调世界时（UTC）时间的SQL函数。它可以帮助我们在处理不同时区之间的时间转换问题时实现准确的转换。

相关问题

insert overwrite table discountdw.dwd_sd_adds_order_bill_inc partition(dt = '2023-06-06') select t1.order_bill_id, t1.counterfoil_no, t1.acceptor, date_format(to_utc_timestamp(cast(t1.expiry_date as bigint) ,'GMT-8'),'YYYY-MM-dd'), t2.company_id, t1.cert_no, t1.company_name, t1.third_order_id, t1.counterfoil_amt/10000, t1.transaction_amt/10000, t1.rate, '3bp' as service_tariffing, ((DATEDIFF(to_utc_timestamp(t1.expiry_date ,'GMT-8'),to_utc_timestamp(t1.transaction_date ,'GMT-8') ) + adjust_days)* 0.0003 *(counterfoil_amt))/ 360 as service_fee, 360 as total_days, DATEDIFF(to_utc_timestamp(t1.expiry_date ,'GMT-8'),to_utc_timestamp(t1.transaction_date ,'GMT-8') ) + adjust_days as modulation_date, t3.channel_type, t3.bank_name, date_format(to_utc_timestamp(cast(t1.transaction_date as bigint) ,'GMT-8'),'YYYY-MM-dd'), t1.order_status_code, t1.order_status_msg, t4.fee_amt, t4.status, t1.tenant_id, t5.revenue, to_utc_timestamp(cast(t1.create_date as bigint) ,'GMT-8'), to_utc_timestamp(cast(t1.update_date as bigint) ,'GMT-8') from (select * from discountdw.ods_adds_order_bill_inc where dt ='2023-06-06' and channel_id=101110004 )t1 left join (select * from mecdw.ods_company_full where platform_id='sdpjw')t2 on t1.cert_no=t2.cert_no and t1.tenant_id=t2.tenant_id left join discountdw.dim_adds_product_full t3 on t1.partner_id=t3.partner_id and t1.product_id=t3.product_id left join (select * from mecdw.dwd_sc_fee_record_full where dt='2023-06-06' and biz_type=2 ) t4 on t1.order_bill_id=t4.third_id left join (select * from discountdw.ods_sd_order_ext_inc where dt='2023-06-06') t5 on t1.order_bill_id=t5.order_bill_id left join sdpjwdw.dim_holiday_info_full t6 on date_format(to_utc_timestamp(t1.expiry_date ,'GMT-8'),'YYYY-MM-dd') = t6.civic_holiday ;

这是一条 SQL 语句，看起来比较长。以下是一些可以考虑优化的建议：

1. 将表名、字段名等缩短，以减少字符数和提高可读性。
2. 将复杂的表连接操作拆分成多个子查询，以降低查询复杂度。
3. 对于一些计算操作，可以考虑使用内置函数或自定义函数，以简化代码并提高可维护性。
4. 对于一些重复的操作，可以将其提取成变量或常量，以减少重复代码。

综上所述，优化后的 SQL 可能类似于以下代码（仅供参考）：

-- 定义常量
SET adjust_days = 1;

-- 查询订单表
WITH order_data AS (
  SELECT
    o.order_bill_id,
    o.counterfoil_no,
    o.acceptor,
    DATE_FORMAT(TO_UTC_TIMESTAMP(CAST(o.expiry_date AS BIGINT), 'GMT-8'), 'YYYY-MM-dd') AS expiry_date,
    o.cert_no,
    o.company_name,
    o.third_order_id,
    o.counterfoil_amt / 10000 AS counterfoil_amt,
    o.transaction_amt / 10000 AS transaction_amt,
    o.rate,
    '3bp' AS service_tariffing,
    ((DATEDIFF(TO_UTC_TIMESTAMP(o.expiry_date, 'GMT-8'), TO_UTC_TIMESTAMP(o.transaction_date, 'GMT-8')) + adjust_days) * 0.0003 * (o.counterfoil_amt)) / 360 AS service_fee,
    360 AS total_days,
    DATEDIFF(TO_UTC_TIMESTAMP(o.expiry_date, 'GMT-8'), TO_UTC_TIMESTAMP(o.transaction_date, 'GMT-8')) + adjust_days AS modulation_date,
    o.order_status_code,
    o.order_status_msg,
    o.tenant_id,
    TO_UTC_TIMESTAMP(CAST(o.create_date AS BIGINT), 'GMT-8') AS create_date,
    TO_UTC_TIMESTAMP(CAST(o.update_date AS BIGINT), 'GMT-8') AS update_date
  FROM discountdw.ods_adds_order_bill_inc o
  WHERE o.dt = '2023-06-06' AND o.channel_id = 101110004
),

-- 查询公司表
company_data AS (
  SELECT
    c.company_id,
    c.cert_no,
    c.tenant_id
  FROM mecdw.ods_company_full c
  WHERE c.platform_id = 'sdpjw'
),

-- 查询产品表
product_data AS (
  SELECT
    p.partner_id,
    p.product_id,
    p.channel_type,
    p.bank_name
  FROM discountdw.dim_adds_product_full p
),

-- 查询费用记录表
fee_data AS (
  SELECT
    f.third_id,
    f.fee_amt,
    f.status
  FROM mecdw.dwd_sc_fee_record_full f
  WHERE f.dt = '2023-06-06' AND f.biz_type = 2
),

-- 查询订单扩展信息表
order_ext_data AS (
  SELECT
    e.order_bill_id,
    e.revenue
  FROM discountdw.ods_sd_order_ext_inc e
  WHERE e.dt = '2023-06-06'
),

-- 查询节假日表
holiday_data AS (
  SELECT
    h.civic_holiday
  FROM sdpjwdw.dim_holiday_info_full h
)

-- 合并数据
INSERT OVERWRITE TABLE discountdw.dwd_sd_adds_order_bill_inc PARTITION(dt = '2023-06-06')
SELECT
  o.order_bill_id,
  o.counterfoil_no,
  o.acceptor,
  o.expiry_date,
  c.company_id,
  o.cert_no,
  o.company_name,
  o.third_order_id,
  o.counterfoil_amt,
  o.transaction_amt,
  o.rate,
  o.service_tariffing,
  o.service_fee,
  o.total_days,
  o.modulation_date,
  p.channel_type,
  p.bank_name,
  DATE_FORMAT(TO_UTC_TIMESTAMP(CAST(o.transaction_date AS BIGINT), 'GMT-8'), 'YYYY-MM-dd'),
  o.order_status_code,
  o.order_status_msg,
  f.fee_amt,
  f.status,
  o.tenant_id,
  e.revenue,
  o.create_date,
  o.update_date
FROM order_data o
LEFT JOIN company_data c ON o.cert_no = c.cert_no AND o.tenant_id = c.tenant_id
LEFT JOIN product_data p ON o.partner_id = p.partner_id AND o.product_id = p.product_id
LEFT JOIN fee_data f ON o.order_bill_id = f.third_id
LEFT JOIN order_ext_data e ON o.order_bill_id = e.order_bill_id
LEFT JOIN holiday_data h ON o.expiry_date = DATE_FORMAT(TO_UTC_TIMESTAMP(h.civic_holiday, 'GMT-8'), 'YYYY-MM-dd');

from_utc_timestamp(ts,'GMT+8')

As an AI language model, I do not have access to a specific timestamp or timezone. However, the syntax for converting a timestamp from UTC to GMT+8 in SQL is:

SELECT from_utc_timestamp(ts, 'Asia/Shanghai') 
FROM your_table_name;

In this case, we are converting the UTC timestamp to the GMT+8 timezone of Asia/Shanghai, which is equivalent to GMT+8.