5cb0e33597
In many functions, a NumericVar was initialized from an input Numeric, to be passed as input to a calculation function. When the NumericVar is not modified, the digits array of the NumericVar can point directly to the digits array in the original Numeric, and we can avoid a palloc() and memcpy(). Add init_var_from_num() function to initialize a var like that. Remove dscale argument from get_str_from_var(), as all the callers just passed the dscale of the variable. That means that the rounding it used to do was not actually necessary, and get_str_from_var() no longer scribbles on its input. That makes it safer in general, and allows us to use the new init_var_from_num() function in e.g numeric_out(). Also modified numericvar_to_int8() to no scribble on its input either. It creates a temporary copy to avoid that. To compensate, the callers no longer need to create a temporary copy, so the net # of pallocs is the same, but this is nicer. In the passing, use a constant for the number 10 in get_str_from_var_sci(), when calculating 10^exponent. Saves a palloc() and some cycles to convert integer 10 to numeric. Original patch by Kyotaro HORIGUCHI, with further changes by me. Reviewed by Pavel Stehule.
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. PostgreSQL has many language interfaces, many of which are listed here: http://www.postgresql.org/download See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Changes between all PostgreSQL releases are recorded in the file HISTORY. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.