I think the fastest solution is select * from table where rand() <= .3 Here is why I think this should do the job. It will create a random number for each row. The number is between 0 and 1 It evaluates whether to display that row if the number generated is between 0 and … Read more
When you do integer division (integer divided by integer) you always get an integer answer. 50/100 = .50, which is 0 in integer-speak. Have you tried dividing MY_COLUMN by 100.0?
As the documentation shows, you can have multiple aggregate function clauses. So you can do this: select * from ( select * from tab1 ) pivot ( count(type) as ct, sum(weight) as wt, sum(height) as ht for type in (‘A’ as A, ‘B’ as B, ‘C’ as C) ); A_CT A_WT A_HT B_CT B_WT B_HT … Read more
You’ll have to implement this as an INSTEAD OF delete trigger on insights, to get it to work. Something like: create trigger T_Insights_D on Insights instead of delete as set nocount on delete from broader_insights_insights where insight_id in (select ID from deleted) or broader_insight_id in (select ID from deleted) delete from Insights where ID in … Read more
Effectively, WHERE conditions and JOIN conditions for [INNER] JOIN are 100 % equivalent in PostgreSQL. (It’s good practice to use explicit JOIN conditions to make queries easier to read and maintain, though). The same is not true for a LEFT JOIN combined with a WHERE condition on a table to the right of the join. … Read more
Since Postgres 9.6, it is possible to specify a collation which will sort columns with numbers naturally. https://www.postgresql.org/docs/10/collation.html — First create a collation with numeric sorting CREATE COLLATION numeric (provider = icu, locale=”[email protected]=yes”); — Alter table to use the collation ALTER TABLE “employees” ALTER COLUMN “em_code” type TEXT COLLATE numeric; Now just query as you … Read more
Try changing LIKE to ALIKE and your wildcard characters from * to %. The Access Database Engine (Jet, ACE, whatever) has two ANSI Query Modes which each use different wildcard characters for LIKE: ANSI-89 Query Mode uses * ANSI-92 Query Mode uses % OLE DB always uses ANSI-92 Query Mode. DAO always uses ANSI-89 Query … Read more
Use a RECURSIVE CTE in Postgres: WITH RECURSIVE cte AS ( SELECT key, value, 1 AS level FROM taxonomy WHERE key = 0 UNION ALL SELECT t.key, t.value, c.level + 1 FROM cte c JOIN taxonomy t ON t.taxHier = c.key ) SELECT value FROM cte ORDER BY level; Details and links to documentation in … Read more
Perhaps you can use Antlr, it has a number of SQL grammars and a Java library, as well as plugins for various Java IDEs. Or as advised, use the parser of open source SQL utilities like SQuirreL SQL Client.
Based on the information in the article you linked to this should work: update giveaways set winner=”1″ where Id = (select Id from (select max(Id) as id from giveaways) as t)