> + same level are considerd to be <firstterm>siblings</firstterm>,
considered
> + <productname>PostgreSQL</productname> specific functions detailed in
postgresql hyphen specific (as in the original)
These would all be easier to read with commas:
+ <parameter>expression</parameter> is NULL an
+ If <literal>WITH UNIQUE</literal> is specified the
+ If the input is NULL an SQL NULL is returned. If the input is a number
+ If <literal>WITH UNIQUE</literal> is specified there must not
+ is <literal>strict</literal> an error is generated if it yields no items.
There's a few instances of "space space" that could be condensed:
+ <function>json_scalar</function> functions, this needs to be either <type>json</type> or
+ which must be a SELECT query returning a single column. If
