I need help understanding the following two release note items (see XXX):
<listitem> <para> Create a general mechanism that supports casts to and from the standard string
types(<type>TEXT</type>, <type>VARCHAR</type>, <type>CHAR</type>) for <emphasis>every</emphasis> datatype, by
invokingthe datatype's I/O functions (Tom) XXX examples? </para>
<para> These new casts are assignment-only in the to-string direction, explicit-only in the other
direction,and therefore should create no surprising behavior. Various datatype-specific casting functions
thatwere equivalent to this behavior were removed. </para> </listitem>
<listitem> <para> Allow limited hashing when using two different data types (Tom) </para>
<para> This allows hash joins, hash indexes, hashed subplans, and hash aggregation to be used in
situationsinvolving cross-data-type comparisons, if the data types have compatible hash functions. Currently,
cross-data-typehashing support exists for <type>smallint</type>/<type>integer</type>/<type>bigint</type>, and
for<type>float4</type>/<type>float8</type>. XXX how do you do hash aggregate with two different data types
</para> </listitem>
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://postgres.enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +