Writing wrapper Postgres function and types to specific kdb+ queries is cumbersome, so convenenient utility functions (both kdb+ and Postgres) are provided with the installation. To reread the settings, the process will need to restart. Note that configuration settings are read initially when a Postgres process loads the extension. The nfig file can be modified to add the following configuration settings. Postgres = # select * from pgtokdb.getstatus('.pgtokdb.status') Kdb+ script placed somewhere convenient to the Q directoriesĪs an example, on my Mac, here are the names of the target directories. Kx Systems C-language DLL to be placed in PATH SQL script that is run when extension is CREATED Shared library to be used for Mac and Linux deploymentsĭescriptive information for the extension The table below summarizes each file in the pgtokdb distribution and the pg_config option to be used to identify their destination. There are a number of options available to pgconfig which return names of directories for distribution files. This utility prints configuration parameters of the currently installed version of PostgreSQL. In order to determine which directories to use, Postgres provides a utility in its bin directory called pg_config. The distribution files have to be placed into a directories that comprise the deployed Postgres installation. Note that Postgres does not have a single-byte data type, so kdb+ type x should be mapped to a Postgres integer type, where it will be up-casted. However there could be precision loss when casting integers to floats. The extension does support up-casting to data types where there won't be any data loss, for example kdb+ short to Postgres bigint.
#Visual studio for mac postgresql code
The Code specifies the single character kdb+ datatype codes, which are used in the genddl functions in the pgtokdb namespace provided in the provided pgtokdb.q script file. The table below summarizes the how the data types should be mapped between kdb+ and Postgres. Postgres = # select j from foo('select sum j from kdbtbl') The \t that follows the q prompt indicates that we want to time the operation. In kdb+, we create a 100 million row table with a single bigint column, containing the numbers from 0 rising monotonically upwards. These tests were run on my circa 2014 Macbook Pro, with an SSD drive. PerformanceĪlthough not very scientific, the following example provides some information on the performance characteristics of the extension, as well as kdb+ and Postgres. 51818 | string9įinally, there are many regression tests in the project test directory that are great examples of show varying data types, arguments, results, and capabilities. Create type callfun_t as (id bigint, vals float8, ts timestamp, str varchar) Ĭreate function callfun( varchar, integer) returns setof callfun_t as 'pgtokdb ', 'getset ' language c
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