005a2907dc
The general case for converting to a JSONB numeric value is to run the source datatype's output function and then numeric_in, but we can do substantially better than that for integer and numeric source values. This patch improves the speed of jsonb_agg by 30% for integer input, and nearly 2X for numeric input. Sadly, the obvious idea of using float4_numeric and float8_numeric to speed up those cases doesn't work: they are actually slower than the generic coerce-via-I/O method, and not by a small amount. They might round off differently than this code has historically done, too. Leave that alone pending possible changes in those functions. We can also do better than the existing code for text/varchar/bpchar source data; this optimization is similar to one that already exists in the json_agg() code. That saves 20% or so for such inputs. Also make a couple of other minor improvements, such as not giving JSONTYPE_CAST its own special case outside the switch when it could perfectly well be handled inside, and not using dubious string hacking to detect infinity and NaN results. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: jian he <jian.universality@gmail.com> Reviewed-by: Chao Li <li.evan.chao@gmail.com> Discussion: https://postgr.es/m/1060917.1753202222@sss.pgh.pa.us
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.