schema.xml 是做什么的？
solr加载数据，创建索引和数据时，核心数据结构的配置文件是schema.xml，该配置文件主要用于配置数据源，字段类型定义，搜索类型定义等。schema.xml的配置直接影响搜索结果的准确性与效率。
fieldType:节点主要用于搜索类型的定义，这里给出schema.xml提供常用类型的定义。
<fieldType name="string" class="solr.StrField" sortMissingLast="true" />
<!-- boolean type: "true" or "false" -->
<fieldType name="boolean" class="solr.BoolField" sortMissingLast="true"/>
<!-- sortMissingLast and sortMissingFirst attributes are optional attributes are
currently supported on types that are sorted internally as strings
and on numeric types.
This includes "string","boolean",and,as of 3.5 (and 4.x),int,float,long,date,double,including the "Trie" variants.
- If sortMissingLast="true",then a sort on this field will cause documents
without the field to come after documents with the field,regardless of the requested sort order (asc or desc).
- If sortMissingFirst="true",then a sort on this field will cause documents
without the field to come before documents with the field,regardless of the requested sort order.
- If sortMissingLast="false" and sortMissingFirst="false" (the default),then default lucene sorting will be used which places docs without the
field first in an ascending sort and last in a descending sort.
-->
<!--
Default numeric field types. For faster range queries,consider the tint/tfloat/tlong/tdouble types.
These fields support doc values,but they require the field to be
single-valued and either be required or have a default value.
-->
<fieldType name="int" class="solr.TrieIntField" precisionStep="0" positionIncrementGap="0"/>
<fieldType name="float" class="solr.TrieFloatField" precisionStep="0" positionIncrementGap="0"/>
<fieldType name="long" class="solr.TrieLongField" precisionStep="0" positionIncrementGap="0"/>
<fieldType name="double" class="solr.TrieDoubleField" precisionStep="0" positionIncrementGap="0"/>
<!--
Numeric field types that index each value at varIoUs levels of precision
to accelerate range queries when the number of values between the range
endpoints is large. See the javadoc for NumericRangeQuery for internal
implementation details.
Smaller precisionStep values (specified in bits) will lead to more tokens
indexed per value,slightly larger index size,and faster range queries.
A precisionStep of 0 disables indexing at different precision levels.
-->
<fieldType name="tint" class="solr.TrieIntField" precisionStep="8" positionIncrementGap="0"/>
<fieldType name="tfloat" class="solr.TrieFloatField" precisionStep="8" positionIncrementGap="0"/>
<fieldType name="tlong" class="solr.TrieLongField" precisionStep="8" positionIncrementGap="0"/>
<fieldType name="tdouble" class="solr.TrieDoubleField" precisionStep="8" positionIncrementGap="0"/>
<!-- The format for this date field is of the form 1995-12-31T23:59:59Z,and
is a more restricted form of the canonical representation of dateTime
http://www.w3.org/TR/xmlschema-2/#dateTime
The trailing "Z" designates UTC time and is mandatory.
Optional fractional seconds are allowed: 1995-12-31T23:59:59.999Z
All other components are mandatory.
Expressions can also be used to denote calculations that should be
performed relative to "NOW" to determine the value,ie...
NOW/HOUR
... Round to the start of the current hour
NOW-1DAY
... Exactly 1 day prior to now
NOW/DAY+6MONTHS+3DAYS
... 6 months and 3 days in the future from the start of
the current day
Consult the DateField javadocs for more information.
Note: For faster range queries,consider the tdate type
-->
<fieldType name="date" class="solr.TrieDateField" precisionStep="0" positionIncrementGap="0"/>
<!-- A Trie based date field for faster date range queries and date faceting. -->
<fieldType name="tdate" class="solr.TrieDateField" precisionStep="6" positionIncrementGap="0"/>
<!--Binary data type. The data should be sent/retrieved in as Base64 encoded Strings -->
<fieldtype name="binary" class="solr.BinaryField"/>
<!--
Note:
These should only be used for compatibility with existing indexes (created with lucene or older Solr versions).
Use Trie based fields instead. As of Solr 3.5 and 4.x,Trie based fields support sortMissingFirst/Last
Plain numeric field types that store and index the text
value verbatim (and hence don't correctly support range queries,since the
lexicographic ordering isn't equal to the numeric ordering)
NOTE: These field types are deprecated will be completely removed in Solr 5.0!
-->
<!--
<fieldType name="pint" class="solr.IntField"/>
<fieldType name="plong" class="solr.LongField"/>
<fieldType name="pfloat" class="solr.FloatField"/>
<fieldType name="pdouble" class="solr.DoubleField"/>
<fieldType name="pdate" class="solr.DateField" sortMissingLast="true"/>
-->
<!-- The "RandomSortField" is not used to store or search any
data. You can declare fields of this type it in your schema
to generate pseudo-random orderings of your docs for sorting
or function purposes. The ordering is generated based on the field
name and the version of the index. As long as the index version
remains unchanged,and the same field name is reused,the ordering of the docs will be consistent.
If you want different psuedo-random orderings of documents,for the same version of the index,use a dynamicField and
change the field name in the request.
-->
<fieldType name="random" class="solr.RandomSortField" indexed="true" />
这里给出的类型有，字符串，bool，int，date等等，基本java常用的都有。下面解释一下各个参数的意思。
name：定义搜索字段名
class：这个搜索字段实际使用的类与方法。在org.appache.solr.analysis包下，包括了常用的类型。
其他可选的属性：
sortMissingLast，sortMissingFirst两个属性是用在可以内在使用String排序的类型上，默认false，适用于字段类型：string,boolean,sint,slong,sfloat,sdouble,pdate。
sortMissingLast="true"，没有该field的数据排在有该field的数据之后，而不管请求时的排序规则，在Java中对应的意思就是，该字段为NULL，排在后面。
sortMissingFirst="true"，排序规则与sortMissingLast相反。
positionIncrementGap：可选属性，定义在同一个文档中此类型数据的空白间隔，避免短语匹配错误。
field:字段用于定义数据源字段所使用的搜索类型与相关设置。
<field name="_version_" type="long" indexed="true" stored="true"/> <!-- points to the root document of a block of nested documents. required for nested document support,may be removed otherwise --> <field name="_root_" type="string" indexed="true" stored="false"/> <!-- Only remove the "id" field if you have a very good reason to. While not strictly required,it is highly recommended. A <uniqueKey> is present in almost all Solr installations. See the <uniqueKey> declaration below where <uniqueKey> is set to "id". --> <field name="id" type="string" indexed="true" stored="true" required="true" multiValued="false" /> <field name="sku" type="text_en_splitting_tight" indexed="true" stored="true" omitNorms="true"/> <field name="name" type="text_general" indexed="true" stored="true"/> <field name="manu" type="text_general" indexed="true" stored="true" omitNorms="true"/> <field name="cat" type="string" indexed="true" stored="true" multiValued="true"/> <field name="features" type="text_general" indexed="true" stored="true" multiValued="true"/> <field name="includes" type="text_general" indexed="true" stored="true" termVectors="true" termPositions="true" termOffsets="true" /> <field name="weight" type="float" indexed="true" stored="true"/> <field name="price" type="float" indexed="true" stored="true"/> <field name="popularity" type="int" indexed="true" stored="true" /> <field name="inStock" type="boolean" indexed="true" stored="true" /> <field name="store" type="location" indexed="true" stored="true"/> <!-- Common Metadata fields,named specifically to match up with SolrCell Metadata when parsing rich documents such as Word,PDF. Some fields are multiValued only because Tika currently may return multiple values for them. Some Metadata is parsed from the documents,but there are some which come from the client context: "content_type": From the HTTP headers of incoming stream "resourcename": From SolrCell request param resource.name --> <field name="title" type="text_general" indexed="true" stored="true" multiValued="true"/> <field name="subject" type="text_general" indexed="true" stored="true"/> <field name="description" type="text_general" indexed="true" stored="true"/> <field name="comments" type="text_general" indexed="true" stored="true"/> <field name="author" type="text_general" indexed="true" stored="true"/> <field name="keywords" type="text_general" indexed="true" stored="true"/> <field name="category" type="text_general" indexed="true" stored="true"/> <field name="resourcename" type="text_general" indexed="true" stored="true"/> <field name="url" type="text_general" indexed="true" stored="true"/> <field name="content_type" type="string" indexed="true" stored="true" multiValued="true"/> <field name="last_modified" type="date" indexed="true" stored="true"/> <field name="links" type="string" indexed="true" stored="true" multiValued="true"/> <!-- Main body of document extracted by SolrCell. NOTE: This field is not indexed by default,since it is also copied to "text" using copyField below. This is to save space. Use this field for returning and highlighting document content. Use the "text" field to search the content. --> <field name="content" type="text_general" indexed="false" stored="true" multiValued="true"/> <!-- catchall field,containing all other searchable text fields (implemented via copyField further on in this schema --> <field name="text" type="text_general" indexed="true" stored="false" multiValued="true"/> <!-- catchall text field that indexes tokens both normally and in reverse for efficient leading wildcard queries. --> <field name="text_rev" type="text_general_rev" indexed="true" stored="false" multiValued="true"/> <!-- non-tokenized version of manufacturer to make it easier to sort or group results by manufacturer. copied from "manu" via copyField --> <field name="manu_exact" type="string" indexed="true" stored="false"/> <field name="payloads" type="payloads" indexed="true" stored="true"/>
name：数据源字段名，搜索使用到。
type：搜索类型名例如中文ika搜索名text_ika，对应于fieldType中的name。不需要分词的字符串类型，string即可，如果需要分词，用上面配置好的分词type。
indexed：是否被索引，只有设置为true的字段才能进行搜索排序分片(earchable,sortable,facetable)。
stored：是否存储内容，如果不需要存储字段值，尽量设置为false以提高效率。
multiValued：是否为多值类型，SOLR允许配置多个数据源字段存储到一个搜索字段中。多个值必须为true，否则有可能抛出异常。
copyField:如果我们的搜索需要搜索多个字段该怎么办呢？这时候，我们就可以使用copyField。
<copyField source="cat" dest="text"/> <copyField source="name" dest="text"/> <copyField source="manu" dest="text"/> <copyField source="features" dest="text"/> <copyField source="includes" dest="text"/> <copyField source="manu" dest="manu_exact"/> <!-- Copy the price into a currency enabled field (default USD) --> <copyField source="price" dest="price_c"/> <!-- Text fields from SolrCell to search by default in our catch-all field --> <copyField source="title" dest="text"/> <copyField source="author" dest="text"/> <copyField source="description" dest="text"/> <copyField source="keywords" dest="text"/> <copyField source="content" dest="text"/> <copyField source="content_type" dest="text"/> <copyField source="resourcename" dest="text"/> <copyField source="url" dest="text"/> <!-- Create a string version of author for faceting --> <copyField source="author" dest="author_s"/>
我们将所有的中文分词字段全部拷贝至all中，当我们进行全文检索是，只用搜索all字段就OK了。
注意，这里的目标字段必须支持多值，最好不要存储，因为他只是做搜索。indexed为true，stored为false。
copyField节点和field节点都在fields节点之内。
问题又来了，如果需要根据不同的重要性进行区分，例如name的重要性比address大，该怎么办呢，后面再说这个问题。
dynamicField:用通配符定义一个field来存在没有被field定义的漏网之鱼
<dynamicField name="*_i" type="int" indexed="true" stored="true"/> <dynamicField name="*_is" type="int" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_s" type="string" indexed="true" stored="true" /> <dynamicField name="*_ss" type="string" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_l" type="long" indexed="true" stored="true"/> <dynamicField name="*_ls" type="long" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_t" type="text_general" indexed="true" stored="true"/> <dynamicField name="*_txt" type="text_general" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_en" type="text_en" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_b" type="boolean" indexed="true" stored="true"/> <dynamicField name="*_bs" type="boolean" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_f" type="float" indexed="true" stored="true"/> <dynamicField name="*_fs" type="float" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_d" type="double" indexed="true" stored="true"/> <dynamicField name="*_ds" type="double" indexed="true" stored="true" multiValued="true"/> <!-- Type used to index the lat and lon components for the "location" FieldType --> <dynamicField name="*_coordinate" type="tdouble" indexed="true" stored="false" /> <dynamicField name="*_dt" type="date" indexed="true" stored="true"/> <dynamicField name="*_dts" type="date" indexed="true" stored="true" multiValued="true"/> <dynamicField name="*_p" type="location" indexed="true" stored="true"/> <!-- some trie-coded dynamic fields for faster range queries --> <dynamicField name="*_ti" type="tint" indexed="true" stored="true"/> <dynamicField name="*_tl" type="tlong" indexed="true" stored="true"/> <dynamicField name="*_tf" type="tfloat" indexed="true" stored="true"/> <dynamicField name="*_td" type="tdouble" indexed="true" stored="true"/> <dynamicField name="*_tdt" type="tdate" indexed="true" stored="true"/> <dynamicField name="*_c" type="currency" indexed="true" stored="true"/> <dynamicField name="ignored_*" type="ignored" multiValued="true"/> <dynamicField name="attr_*" type="text_general" indexed="true" stored="true" multiValued="true"/> <dynamicField name="random_*" type="random" />uniqueKey:solr必须设置一个唯一字段，常设置为id，此唯一一段有uniqueKey节点指定。
<uniqueKey>id</uniqueKey>defaultSearchField:默认搜索的字段，我们已经将需要搜索的字段拷贝至all字段了，在这里设为all即可。
<defaultSearchField>text</defaultSearchField>
solrQueryParser:认搜索操作符参数，及搜索短语间的逻辑，用AND增加准确率，用OR增加覆盖面，建议用AND，也可在搜索语句中定义。例如搜索“河西 万达”，使用AND默认搜索为“河西AND万达“。<solrQueryParser defaultOperator="OR"/>
