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==========================
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The default query language
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==========================
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A query consists of *terms* and *operators*. There are two types of terms: single
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terms and *phrases*. Multiple terms can be combined with operators such as
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Whoosh supports indexing text in different *fields*. You must specify the
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*default field* when you create the :class:`whoosh.qparser.QueryParser` object.
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This is the field in which any terms the user does not explicitly specify a field
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Individual terms and phrases
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============================
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Find documents containing the term ``render``::
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Find documents containing the phrase ``all was well``::
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Note that a field must store Position information for phrase searching to work in
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Find documents containing ``render`` *and* ``shading``::
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Note that AND is the default relation between terms, so this is the same as::
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Find documents containing ``render``, *and* also either ``shading`` *or*
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render AND shading OR modeling
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Find documents containing ``render`` but *not* modeling::
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Find documents containing ``alpha`` but not either ``beta`` or ``gamma``::
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alpha NOT (beta OR gamma)
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Note that when no boolean operator is specified between terms, the parser will
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insert one, by default AND. So this query::
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render shading modeling
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is equivalent (by default) to::
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render AND shading AND modeling
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See :doc:`customizing the default parser <parsing>` for information on how to
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change the default operator to OR.
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Group operators together with parentheses. For example to find documents that
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contain both ``render`` and ``shading``, or contain ``modeling``::
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(render AND shading) OR modeling
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Find the term ``ivan`` in the ``name`` field::
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The ``field:`` prefix only sets the field for the term it directly precedes, so
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Will search for ``open`` in the ``title`` field and ``sesame`` in the *default*
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To apply a field prefix to multiple terms, group them with parentheses::
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title:open title:sesame
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Of course you can specify a field for phrases too::
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Use "globs" (wildcard expressions using ``?`` to represent a single character
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and ``*`` to represent any number of characters) to match terms::
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Note that a wildcard starting with ``?`` or ``*`` is very slow. Note also that
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these wildcards only match *individual terms*. For example, the query::
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will **not** match an indexed phrase like::
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because those are four separate terms.
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You can match a range of terms. For example, the following query will match
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documents containing terms in the lexical range from ``apple`` to ``bear``
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*inclusive*. For example, it will match documents containing ``azores`` and
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``be`` but not ``blur``::
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This is very useful when you've stored, for example, dates in a lexically sorted
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format (i.e. YYYYMMDD)::
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date:[20050101 TO 20090715]
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The range is normally *inclusive* (that is, the range will match all terms
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between the start and end term, *as well as* the start and end terms
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themselves). You can specify that one or both ends of the range are *exclusive*
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by using the ``{`` and/or ``}`` characters::
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You can also specify *open-ended* ranges by leaving out the start or end term::
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Boosting query elements
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=======================
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You can specify that certain parts of a query are more important for calculating
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the score of a matched document than others. For example, to specify that
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``ninja`` is twice as important as other words, and ``bear`` is half as
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ninja^2 cowboy bear^0.5
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You can apply a boost to several terms using grouping parentheses::
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(open sesame)^2.5 roc
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Making a term from literal text
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===============================
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If you need to include characters in a term that are normally treated specially
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the by the parser, such as spaces, colons, or brackets, you can enclose the term
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path:'MacHD:My Documents'
added
removed
docs/build/html/_sources/querylang.txt
