[[query-dsl-simple-query-string-query]]
=== Simple Query String Query

A query that uses the SimpleQueryParser to parse its context. Unlike the
regular `query_string` query, the `simple_query_string` query will never
throw an exception, and discards invalid parts of the query. Here is
an example:

[source,js]
--------------------------------------------------
GET /_search
{
  "query": {
    "simple_query_string" : {
        "query": "\"fried eggs\" +(eggplant | potato) -frittata",
        "analyzer": "snowball",
        "fields": ["body^5","_all"],
        "default_operator": "and"
    }
  }
}
--------------------------------------------------
// CONSOLE

The `simple_query_string` top level parameters include:

[cols="<,<",options="header",]
|=======================================================================
|Parameter |Description
|`query` |The actual query to be parsed. See below for syntax.

|`fields` |The fields to perform the parsed query against. Defaults to the
`index.query.default_field` index settings, which in turn defaults to `_all`.

|`default_operator` |The default operator used if no explicit operator
is specified. For example, with a default operator of `OR`, the query
`capital of Hungary` is translated to `capital OR of OR Hungary`, and
with default operator of `AND`, the same query is translated to
`capital AND of AND Hungary`. The default value is `OR`.

|`analyzer` |The analyzer used to analyze each term of the query when
creating composite queries.

|`flags` |Flags specifying which features of the `simple_query_string` to
enable. Defaults to `ALL`.

|`analyze_wildcard` | Whether terms of prefix queries should be automatically
analyzed or not. If `true` a best effort will be made to analyze the prefix. However,
some analyzers will be not able to provide a meaningful results
based just on the prefix of a term. Defaults to `false`.

|`lenient` | If set to `true` will cause format based failures
(like providing text to a numeric field) to be ignored.

|`minimum_should_match` | The minimum number of clauses that must match for a
 document to be returned. See the
 <<query-dsl-minimum-should-match,`minimum_should_match`>> documentation for the
 full list of options.

|`quote_field_suffix` | A suffix to append to fields for quoted parts of
the query string. This allows to use a field that has a different analysis chain
for exact matching. Look <<mixing-exact-search-with-stemming,here>> for a
comprehensive example.

|`all_fields` | Perform the query on all fields detected in the mapping that can
be queried. Will be used by default when the `_all` field is disabled and no
`default_field` is specified index settings, and no `fields` are specified.
|=======================================================================

[float]
===== Simple Query String Syntax
The `simple_query_string` supports the following special characters:

* `+` signifies AND operation
* `|` signifies OR operation
* `-` negates a single token
* `"` wraps a number of tokens to signify a phrase for searching
* `*` at the end of a term signifies a prefix query
* `(` and `)` signify precedence
* `~N` after a word signifies edit distance (fuzziness)
* `~N` after a phrase signifies slop amount

In order to search for any of these special characters, they will need to
be escaped with `\`.

Be aware that this syntax may have a different behavior depending on the
`default_operator` value. For example, consider the following query:

[source,js]
--------------------------------------------------
GET /_search
{
    "query": {
        "simple_query_string" : {
            "fields" : ["content"],
            "query" : "foo bar -baz"
        }
    }
}
--------------------------------------------------
// CONSOLE

You may expect that documents containing only "foo" or "bar" will be returned,
as long as they do not contain "baz", however, due to the `default_operator`
being OR, this really means "match documents that contain "foo" or documents
that contain "bar", or documents that don't contain "baz". If this is unintended
then the query can be switched to `"foo bar +-baz"` which will not return
documents that contain "baz".

[float]
==== Default Field
When not explicitly specifying the field to search on in the query
string syntax, the `index.query.default_field` will be used to derive
which field to search on. It defaults to `_all` field.

If the `_all` field is disabled and no `fields` are specified in the request`,
the `simple_query_string` query will automatically attempt to determine the
existing fields in the index's mapping that are queryable, and perform the
search on those fields.

[float]
==== Multi Field
The fields parameter can also include pattern based field names,
allowing to automatically expand to the relevant fields (dynamically
introduced fields included). For example:

[source,js]
--------------------------------------------------
GET /_search
{
    "query": {
        "simple_query_string" : {
            "fields" : ["content", "name.*^5"],
            "query" : "foo bar baz"
        }
    }
}
--------------------------------------------------
// CONSOLE

[float]
==== Flags
`simple_query_string` support multiple flags to specify which parsing features
should be enabled. It is specified as a `|`-delimited string with the
`flags` parameter:

[source,js]
--------------------------------------------------
GET /_search
{
    "query": {
        "simple_query_string" : {
            "query" : "foo | bar + baz*",
            "flags" : "OR|AND|PREFIX"
        }
    }
}
--------------------------------------------------
// CONSOLE

The available flags are: `ALL`, `NONE`, `AND`, `OR`, `NOT`, `PREFIX`, `PHRASE`,
`PRECEDENCE`, `ESCAPE`, `WHITESPACE`, `FUZZY`, `NEAR`, and `SLOP`.