The PostgreSQL EXTRACT() function is used to retrieves subfields such as year or hour from date/time values. The source must be a value expression of type timestamp, time, or interval. The field is an identifier or string that selects what field to be extracted from the source value. Th...
PostgreSQL provides a built-in function namedSUBSTRING()that extracts a substring from any specific string. TheSUBSTRING()function accepts three parameters: a string, starting position, and length. The starting position” and “length” parameters are optional that can be skipped depending on ...
The RIGHT() function is used to extract the rightmost 4 characters from the phone_number column. The phone_number column is assumed to store phone numbers. The result set will contain one column labeled as "Ph.No." with the last 4 digits of the phone numbers for each employee in the em...
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select id, date, another_info from ( select id, date, another_info, row_number() over (partition by id order by date desc) as rn from the_table ) t where rn = 1 order by id; The solution with a window function is in most cases faster than using a sub-query. ...
Let's try to explain the weird result in PostgreSQL 11 when extracting seconds from a timestamp without time zone based on the documentation. As shown below, the offset is 28800 seconds, i.e. 8 hours, which is exactly the sameutc_offsetof the local time zone PRC. ...
const { extractSchemas } = require('extract-pg-schema'); async function run() { const connection = { host: 'localhost', database: 'postgres', user: 'postgres', password: 'postgres', }; const result = await extractSchemas(connection); console.log(result); } run(); For an example of...
2.2. regexp_replace函数,比较简单,难的是里面参数正则表达式的书写。 select case when regexp_replace(uniscid,'[0-9A-HJ-NPQRTUWXY]{2}\\d{6}[0-9A-HJ-NPQRTUWXY]{10}','~~fbietl~~') = '~~fbietl~~' then uniscid else null end uniscid, ...
PostgreSQL Execution mode queue JoffcomcommentedMar 8, 2025 Hey@Fank, We have created an internal ticket to look into this which we will be tracking as "GHC-1110" Joffcomadded thein linearlabelMar 8, 2025 Author FankcommentedMar 8, 2025 ...
E.g. MySQL and PostgreSQL don't expose this behaviour but clearly distinguish between SQLNULLand JSONnull. As doing this in PostgreSQL: postgres=#SELECT '[1, 2, null]'::JSON->3;?column?---(1row) postgres=#SELECT '[1, 2]'::JSON->3;?column?---(1row) Has the exact same behavio...