Query DSL 查询 DSL

Elasticsearch 提供了一个功能全面的查询 DSL，这个查询 DSL 采用 JSON 格式来定义查询条件。你可以把查询 DSL 理解为一个查询的 AST,并由下面 2 中子类组成：

• 子叶型

  子叶查询可以在特定的字段中查找特定的值，这类的查询有诸如 match 查询，term 查询或着 range 查询等。这类查询也支持嵌套查询

• 混合型

  这边翻译地有点拗口，推荐看原文 混合型查询会包装多个子叶型查询或者其他混合型查询。这会使得子查询的查询条件被组合（比如 bool 查询或者 dis_max查询）或者被反转（比如 not 或者 constant_score 查询）。

查询子句的行为会因为它们究竟是被用来 查询内容还是过滤内容 而各不相同。

Elasticsearch provides a full Query DSL based on JSON to define queries. Think of the Query DSL as an AST of queries, consisting of two types of clauses:

• Leaf query clauses

  Leaf query clauses look for a particular value in a particular field, such as the match, term or range queries. These queries can be used by themselves.

• Compound query clauses

  Compound query clauses wrap other leaf or compound queries and are used to combine multiple queries in a logical fashion (such as the bool or dis_max query), or to alter their behaviour (such as the not or constant_score query).

Query clauses behave differently depending on whether they are used in query context or filter context.