hologres时间函数哪些事
---获取某个月最后一天最后时刻的时间戳
date_trunc('month', (current_date-interval '4 month')) :: TIMESTAMP + INTERVAL '1 month - 1 second' AS month_last_timestamp
SELECT
to_timestamp('2021-07-17 17:40:33','yyyy-MM-dd hh24:mi:ss') as "将 string 转成时间戳格式",
to_date(TO_CHAR(to_timestamp(max(event_time)/1000),'yyyy-MM-dd'),'YY MM DD') as "将 long 类型转换成时间戳",
current_date-1 as 昨天,
current_date-to_date(TO_CHAR(to_timestamp(max(event_time)/1000),'yyyy-MM-dd'),'YY MM DD') as 相差几天,
substring(cast(now() as varchar),0,11) as curr_day,
to_char(current_date,'YYYY-MM-DD') as time2, --将date类型转换成字符串
cast(TO_CHAR(CURRENT_TIMESTAMP-regist_time,'dd') as integer)*1.0/365 as age, 利用timestamp直接加减计算天数/365=年龄
corp_id,
now(),
--字符串转long类型
event_time >= EXTRACT(epoch from (TIMESTAMP '2022-01-01 00:00:00'))*1000,
--- 获取整点的时间戳(1651420800000=2022-5-2 0:0:0)
EXTRACT(epoch from cast(current_date -interval '1 month' AS TIMESTAMPTZ))*1000,
date_part('week',TIMESTAMP '2021-03-11'), --获取周数
date_trunc('week', '2021-03-11'::timestamp), --获取周时间
to_date(TO_CHAR(event_time,'yyyy-MM-dd'),'YY MM DD'), -- 将timestamp转化成date类型
EXTRACT(epoch FROM to_timestamp('2021-06-16', 'YYYY-MM-DD')) as day_time_ms -- 将字符串转成时间戳
FROM "flow"."ods_flow_web_active_log"
group by corp_id
### regist_time是TIMESTAMP类型，关于 TIMESTAMP 的条件搜索
select
regist_time
from boss.ods_company
where regist_time >=TIMESTAMP '2010-06-01 00:00:00' and regist_time<=TIMESTAMP '2017-11-02 23:59:59'
order by regist_time asc
### 根据日期 获取 周
select
corp_id,
count(1) as weekly_bo_change_count
from app.ods_bizdata_op_log
where extract(DOW FROM current_timestamp)=1 --- pgsql判断，当前日期是否是[周一]
and to_timestamp(event_time/1000)to_timestamp(cast(CURRENT_TIMESTAMP::DATE-7 as varchar),'yyyy-MM-dd')
group by corp_id
hologres 行转列拼接字符串的问题 string_agg()=group_concat()
SELECT
concat('{',
'"engineCode":"',engine_code,'",',
'"batchNo":"',batch_no,'",',
'"operationType":',operation_type,',',
'"operator":{',
'"id":"',operator_id,'",',
'"type":',operator_type,',',
'"name":"',operator_name,'"',
'},',
'"bizObjectId":"',biz_object_id,'",',
'"bizObjectTitle":"',biz_object_title,'",',
'"operationTime":',operation_time,',',
'"properties":[',
string_agg(concat('{',
'"dataType":',property_data_type,',',
'"code":"',property_code,'",',
'"name":"',property_name,'",',
'"after":"',property_after,'",',
'"before":"',property_before,'"',
'}'),','),
']}')
FROM
tst.ods_engine_bizdatachanged_log
WHERE
engine_code = 'c0000000000up9-0'
AND schema_code = 'smzbx1k6n9x324az3a'
AND biz_object_id='60daf0ec88f9545ac8000001'
AND pt>'20210628'
GROUP BY engine_code,schema_code,biz_object_id,batch_no,operation_type,operator_id,operator_type,operator_name,biz_object_title,operation_time
ORDER BY operation_time DESC
hologress 插入跟新sql
INSERT into boss.ods_xxx_table (name,address,geohashcode,location)
VALUES(?, ?, ?, ?)
on conflict(name)
do
update set
name=excluded.name,
address=excluded.address,
geohashcode=excluded.geohashcode,
location=excluded.location
A表跟新B表
--- PostgreSQL官网
https://www.postgresql.org/docs/9.1/sql-update.html?spm=holoweb.holoweb-cn-hangzhou.help.13.78155ab0jSP1cb
update boss.ods_company_location_distribution f1 set
geohashcode=f2.geohashcode,
location=f2.location,
address=f2.address,
update_time=CURRENT_TIMESTAMP
from map.ods_aiqicha_source_data f2
where f2.cmp_name=f1.name
and f2.is_match='成功'
and length(f1.geohashcode)<=5 -- 排除已经算过的情况
and length(f2.geohashcode)>5; -- 排除更新集合本身就是错误的情况
字符串的替换(将','替换成'#'的操作)
update map.map_business_area_data set location=translate(location,',','#')
where wtime='2021-10-28'
PostgreSQL自定义函数
CREATE OR REPLACE FUNCTION is_json(input_text varchar) RETURNS boolean AS
$$
DECLARE
maybe_json json;
BEGIN
BEGIN
maybe_json := input_text;
EXCEPTION WHEN others THEN
RETURN FALSE;
END;
RETURN TRUE;
END;
$$ LANGUAGE plpgsql IMMUTABLE;
