33f43725fb
better handling of NULL elements within the arrays. The third parameter is a string that should be used to represent a NULL element, or should be translated into a NULL element, respectively. If the third parameter is NULL it behaves the same as the two-parameter form. There are two incompatible changes in the behavior of the two-parameter form of string_to_array. First, it will return an empty (zero-element) array rather than NULL when the input string is of zero length. Second, if the field separator is NULL, the function splits the string into individual characters, rather than returning NULL as before. These two changes make this form fully compatible with the behavior of the new three-parameter form. Pavel Stehule, reviewed by Brendan Jurd
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/.