ow, really nice :) it solve the problem, thanks sergei! 2016-01-20 10:30 GMT-02:00 Sergei Golubchik <[email protected]>:
> Hi, Roberto! > > On Jan 20, Roberto Spadim wrote: > > Hi guys! There's a "easy/fast" way to rewrite a query from this: > > > > Select datetime,key,value from table where ... > > > > To this: > > > > Select datetime, value1 as key1, value2 as key2, .... From table where > ... > > > > I don't remember the right name in R/python (pandas) language but it's > > something like vector/matrix merge > > > > The ideia is, instead of one line of date key vale, use a single date, > and > > "put" values as columns, and the columns name is the key name > > > > The table structure is something like: > > Create table ( > > Datetime datetime not null, > > Key varchar(255) not null, > > Value double not null, > > Primary key(datetime,key) > > ) > > > > Any idea is wellcome > > I know there's many solutions, if i have >100 columns, if datetime is > > sparse (only one key have values per datetime value), etc etc > > Check the PIVOT table type of the CONNECT engine. > https://mariadb.com/kb/en/mariadb/connect-table-types-pivot-table-type/ > > Regards, > Sergei > Chief Architect MariaDB > and [email protected] > -- > Vote for my Percona Live 2016 talks: > > https://www.percona.com/live/data-performance-conference-2016/sessions/mariadb-connectors-fast-and-smart-new-protocol-optimizations#community-voting > > https://www.percona.com/live/data-performance-conference-2016/sessions/mariadb-101-security-validation-authentication-encryption#community-voting > -- Roberto Spadim SPAEmpresarial - Software ERP Eng. Automação e Controle
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