selectdate_trunc('hour', now()); selectdate_trunc('day', timestamp'2022-09-28 14:25:01'); 参考: http://postgres.cn/docs/9.4/functions-datetime.html
https://www.postgresql.org/docs/current/functions-datetime.html#FUNCTIONS-DATETIME-CURRENT 9.9.4. Current Date/Time PostgreSQL provides a number of functions that return values related to the current date and time. These SQL-standard functions all return values based on the start time of the curr...
current_timestamp 同 now() 函数等效。 david=#selectcurrent_timestamp; now---2013-04-1215:40:22.398709+08(1row) david=# 1.2 获取当前日期 select current_date; david=#selectcurrent_date; date---2013-04-12(1row) david=# 1.3 获取当前时间 select current_time; david=#selectcurrent_time; tim...
Datum、date、time 类型的转换以及输入输出函数,上面的将typedef int32 DateADT输出“yyyy-mm-dd” /* * Macros for fmgr-callable functions. * * For TimeADT, we make use of the same support routines as for float8 or int64. * Therefore TimeADT is pass-by-reference if and only if float8 or...
current_timestamp 同 now() 函数等效。 david=#selectcurrent_timestamp; now---2013-04-1215:40:22.398709+08(1row) david=# 1.2 获取当前日期 select current_date; david=#selectcurrent_date; date---2013-04-12(1row) david=# 1.3 获取当前时间 select current_time; david=#select...
Database object location functions Database object size functions Date/Time functions and operators CLOCK_TIMESTAMP() JUSTIFY_DAYS(), JUSTIFY_HOURS(), JUSTIFY_INTERVAL() PG_SLEEP() TRANSACTION_TIMESTAMP() ENUM support functions Geometric functions and operators ...
integer | funcpublic | film_not_in_stock | SETOF integer | p_film_id integer, p_store_id integer, OUT p_film_count integer | funcpublic | get_customer_balance | numeric | p_customer_id integer, p_effective_date timestamp with time zone | funcpublic | inventory...
所有下文描述的接受time或timestamp输入的函数和操作符实际上都有两种变体:一种接收time with time zone或timestamp with time zone, 另外一种接受time without time zone或者timestamp without time zone。为了简化,这些变种没有被独立地展示。此外,+和``操作符都是可交换的操作符对(例如,date+integer和integer+dat...
TIME –use the TIME datatype to manage the time of day values. UUID –guide you on how to use UUID datatype and how to generate UUID values using supplied modules. Array –show you how to work with arrays and introduce you to some handy functions for array manipulation. hstore –introdu...
SELECT CURRENT_DATE; 使用时间函数获取系统当期日期(返回时带时区),输入语句如下: SELECT CURRENT_TIME; 使用时间函数获取系统当期日期(返回时不带时区),输入语句如下: SELECT LOCALTIME; 2、返回当前日期和时间的函数 使用日期时间函数获取当前系统日期和时间,输入语句如下: ...