This is a document for PGroonga 1.X. See PGroonga 2.x document when you're using recent PGroonga.
pgroonga.snippet_html functionpgroonga.snippet_html function returns texts around keywords from target text. It's also known as KWIC (keyword in context). You can see it in search result on Web search engine.
Here is the syntax of this function:
text[] pgroonga.snippet_html(target, ARRAY[keyword1, keyword2, ...])
target is a text type value. pgroonga.snippet_html extracts keywords with around texts from target.
keyword1, keyword2, ... are an array of text type. The keywords to be extracted from target. You must specify one or more keywords.
pgroonga.snippet_html returns an array of text type.
Element in the returned array is a text around keyword.
The keywords are surrounded with <span class="keyword"> and </span>. <, >, & and " in target is HTML escaped.
The maximum size of part of target in each element is 200 bytes. Its unit is byte not the number of characters. Each element may be lager than 200 bytes because each element includes <span class="keyword"> and </span> and may have HTML escaped values. If < is HTML escaped to <, the byte size is increased to 4 from 1.
See examples in tutorial.