RediSearch Full Command Documentation

Create

FT.CREATE

Format

  1.   FT.CREATE {index} 
  2.     [ON {structure}]
  3.        [PREFIX {count} {prefix} [{prefix} ..]
  4.        [FILTER {filter}]
  5.        [LANGUAGE {default_lang}]
  6.        [LANGUAGE_FIELD {lang_field}]
  7.        [SCORE {default_score}]
  8.        [SCORE_FIELD {score_field}]
  9.        [PAYLOAD_FIELD {payload_field}]
  10.     [MAXTEXTFIELDS] [TEMPORARY {seconds}] [NOOFFSETS] [NOHL] [NOFIELDS] [NOFREQS] [SKIPINITIALSCAN]
  11.     [STOPWORDS {num} {stopword} ...]
  12.     SCHEMA {field} [TEXT [NOSTEM] [WEIGHT {weight}] [PHONETIC {matcher}] | NUMERIC | GEO | TAG [SEPARATOR {sep}] ] [SORTABLE][NOINDEX] ...

Description

Creates an index with the given spec.

Note on field number limits

RediSearch supports up to 1024 fields per schema, out of which at most 128 can be TEXT fields. On 32 bit builds, at most 64 fields can be TEXT fields. Note that the more fields you have, the larger your index will be, as each additional 8 fields require one extra byte per index record to encode. You can always use the NOFIELDS option and not encode field information into the index, for saving space, if you do not need filtering by text fields. This will still allow filtering by numeric and geo fields.

Note on running in clustered databases

When having several indices in a clustered database, you need to tag the index key and the document key to ensure they reside on the same shard.

sql FT.CREATE {idx} ... PREFIX 1 doc: ... HSET {idx} doc:1{idx} ...

When Running RediSearch in clustered database, there is the ability to span the index across shards. In this case the above does not apply.

Example
  1. FT.CREATE idx ON HASH PREFIX 1 doc: SCHEMA name TEXT SORTABLE age NUMERIC SORTABLE myTag TAG SORTABLE

Parameters

  • index : the index name to create. If it exists the old spec will be overwritten

  • ON {structure} currently supports only HASH (default)

  • PREFIX {count} {prefix} tells the index which keys it should index. You can add several prefixes to index. Since the argument is optional, the default is * (all keys)

  • FILTER {filter} is a filter expression with the full RediSearch aggregation expression language. It is possible to use @__key to access the key that was just added/changed. A field can be used to set field name by passing 'FILTER @indexName=="myindexname"'

  • LANGUAGE {default_lang} : If set indicates the default language for documents in the index. Default to English.

  • LANGUAGE_FIELD {lang_field} : If set indicates the document field that should be used as the document language.

Supported languages

A stemmer is used for the supplied language during indexing. If an unsupported language is sent, the command returns an error. The supported languages are:

“arabic”, “danish”, “dutch”, “english”, “finnish”, “french”, “german”, “hungarian”, “italian”, “norwegian”, “portuguese”, “romanian”, “russian”, “spanish”, “swedish”, “tamil”, “turkish” “chinese”

If indexing a Chinese language document, you must set the language to chinese in order for Chinese characters to be tokenized properly.

##### Adding Chinese Documents

When adding Chinese-language documents, LANGUAGE chinese should be set in order for the indexer to properly tokenize the terms. If the default language is used then search terms will be extracted based on punctuation characters and whitespace. The Chinese language tokenizer makes use of a segmentation algorithm (via Friso ) which segments texts and checks it against a predefined dictionary. See Stemming for more information.

  • SCORE {default_score} : If set indicates the default score for documents in the index. Default score is 1.0.

  • SCORE_FIELD {score_field} : If set indicates the document field that should be used as the document’s rank based on the user’s ranking. Ranking must be between 0.0 and 1.0. If not set the default score is 1.

  • PAYLOAD_FIELD {payload_field} : If set indicates the document field that should be used as a binary safe payload string to the document, that can be evaluated at query time by a custom scoring function, or retrieved to the client.

  • MAXTEXTFIELDS : For efficiency, RediSearch encodes indexes differently if they are created with less than 32 text fields. This option forces RediSearch to encode indexes as if there were more than 32 text fields, which allows you to add additional fields (beyond 32) using FT.ALTER .

  • NOOFFSETS : If set, we do not store term offsets for documents (saves memory, does not allow exact searches or highlighting). Implies NOHL .

  • TEMPORARY : Create a lightweight temporary index which will expire after the specified period of inactivity. The internal idle timer is reset whenever the index is searched or added to. Because such indexes are lightweight, you can create thousands of such indexes without negative performance implications and therefore you should consider using SKIPINITIALSCAN to avoid costly scanning.

Note about deleting a temporary index

When dropped, a temporary index does not delete the hashes as they may have been indexed in several indexes. Adding the DD flag will delete the hashes as well.

  • NOHL : Conserves storage space and memory by disabling highlighting support. If set, we do not store corresponding byte offsets for term positions. NOHL is also implied by NOOFFSETS .

  • NOFIELDS : If set, we do not store field bits for each term. Saves memory, does not allow filtering by specific fields.

  • NOFREQS : If set, we avoid saving the term frequencies in the index. This saves memory but does not allow sorting based on the frequencies of a given term within the document.

  • STOPWORDS : If set, we set the index with a custom stopword list, to be ignored during indexing and search time. {num} is the number of stopwords, followed by a list of stopword arguments exactly the length of {num}.

    If not set, we take the default list of stopwords.

    If {num} is set to 0, the index will not have stopwords.

  • SKIPINITIALSCAN : If set, we do not scan and index.

  • SCHEMA {field} {options…} : After the SCHEMA keyword we define the index fields. They can be numeric, textual or geographical. For textual fields we optionally specify a weight. The default weight is 1.0.

    Field Options

    • SORTABLE

      Numeric, tag or text field can have the optional SORTABLE argument that allows the user to later sort the results by the value of this field (this adds memory overhead so do not declare it on large text fields).

    • NOSTEM

      Text fields can have the NOSTEM argument which will disable stemming when indexing its values. This may be ideal for things like proper names.

    • NOINDEX

      Fields can have the NOINDEX option, which means they will not be indexed. This is useful in conjunction with SORTABLE , to create fields whose update using PARTIAL will not cause full reindexing of the document. If a field has NOINDEX and doesn’t have SORTABLE, it will just be ignored by the index.

    • PHONETIC {matcher}

      Declaring a text field as PHONETIC will perform phonetic matching on it in searches by default. The obligatory {matcher} argument specifies the phonetic algorithm and language used. The following matchers are supported:

      • dm:en - Double Metaphone for English
      • dm:fr - Double Metaphone for French
      • dm:pt - Double Metaphone for Portuguese
      • dm:es - Double Metaphone for Spanish

      For more details see Phonetic Matching .

    • WEIGHT {weight}

      For TEXT fields, declares the importance of this field when calculating result accuracy. This is a multiplication factor, and defaults to 1 if not specified.

    • SEPARATOR {sep}

      For TAG fields, indicates how the text contained in the field is to be split into individual tags. The default is , . The value must be a single character.

Complexity

O(1)

Returns

OK or an error

Insert

HSET/HSETNX/HDEL/HINCRBY/HDECRBY

Format

  1. HSET {hash} {field} {value} [{field} {value} ...]

Description

Since RediSearch v2.0, native redis commands are used to add, update or delete hashes using HSET , HINCRBY , HDEL or other hash commands which alter the hash.

If a hash is modified, all matching indexes are updated automatically. Deletion of a hash by redis, whether by calling DEL , expiring a hash or evicting one, is handled automatically as well.

If a field fails to be indexed (for example, if a numeric fields gets a string value) the whole document is not indexed. FT.INFO provides the number of document-indexing-failures under hash_indexing_failures .

Beware - enabling this feature will slow the whole server by a few points. Only use if hashes are updated often in fields that are not in schema.

If LANGUAGE_FIELD , SCORE_FIELD , or PAYLOAD_FIELD were used with FT.CREATE , the document will extract the properties. A field can be used to get the name of the index it belongs to.

Schema mismatch

If a value in a hash does not match the schema type for that field, indexing of the hash will fail. The number of ‘failed’ document is under hash_indexing_failures at FT.INFO .

Complete list of redis commands which might modify the index:

HSET, HMSET, HSETNX, HINCRBY, HINCRBYFLOAT, HDEL, DEL, SET, RENAME_FROM, RENAME_TO, TRIMMED, RESTORE, EXPIRED, EVICTED, CHANGE, LOADED

Example
  1. HSET doc1 cs101 "hello world" number 3.141 geopoint 39.721717,21.630616 tags foo,bar,baz 
  2. HSET doc2 cs201 "foo bar baz" number 2.718 geopoint "31.433363,35.331942" tags foo,bar,baz
  3. HSET doc3 Name "RedisLabs" indexName "myindexname"

Search

FT.SEARCH

Format

  1. FT.SEARCH {index} {query} [NOCONTENT] [VERBATIM] [NOSTOPWORDS] [WITHSCORES] [WITHPAYLOADS] [WITHSORTKEYS]
  2.   [FILTER {numeric_field} {min} {max}] ...
  3.   [GEOFILTER {geo_field} {lon} {lat} {radius} m|km|mi|ft]
  4.   [INKEYS {num} {key} ... ]
  5.   [INFIELDS {num} {field} ... ]
  6.   [RETURN {num} {field} ... ]
  7.   [SUMMARIZE [FIELDS {num} {field} ... ] [FRAGS {num}] [LEN {fragsize}] [SEPARATOR {separator}]]
  8.   [HIGHLIGHT [FIELDS {num} {field} ... ] [TAGS {open} {close}]]
  9.   [SLOP {slop}] [INORDER]
  10.   [LANGUAGE {language}]
  11.   [EXPANDER {expander}]
  12.   [SCORER {scorer}] [EXPLAINSCORE]
  13.   [PAYLOAD {payload}]
  14.   [SORTBY {field} [ASC|DESC]]
  15.   [LIMIT offset num]

Description

Searches the index with a textual query, returning either documents or just ids.

Example

  1. FT.SEARCH idx "@text:morphix=>{$phonetic:false}"

Parameters

  • index : The index name. The index must be first created with FT.CREATE .

  • query : the text query to search. If it’s more than a single word, put it in quotes. Refer to query syntax for more details.

  • NOCONTENT : If it appears after the query, we only return the document ids and not the content. This is useful if RediSearch is only an index on an external document collection

  • VERBATIM : if set, we do not try to use stemming for query expansion but search the query terms verbatim.

  • NOSTOPWORDS : If set, we do not filter stopwords from the query.
  • WITHSCORES : If set, we also return the relative internal score of each document. this can be used to merge results from multiple instances
  • WITHPAYLOADS : If set, we retrieve optional document payloads (see FT.ADD). the payloads follow the document id, and if WITHSCORES was set, follow the scores.

  • WITHSORTKEYS : Only relevant in conjunction with SORTBY . Returns the value of the sorting key, right after the id and score and /or payload if requested. This is usually not needed by users, and exists for distributed search coordination purposes.

  • FILTER numeric_field min max : If set, and numeric_field is defined as a numeric field in FT.CREATE, we will limit results to those having numeric values ranging between min and max. min and max follow ZRANGE syntax, and can be -inf , +inf and use ( for exclusive ranges. Multiple numeric filters for different fields are supported in one query.

  • GEOFILTER {geo_field} {lon} {lat} {radius} m|km|mi|ft : If set, we filter the results to a given radius from lon and lat. Radius is given as a number and units. See GEORADIUS for more details.

  • INKEYS {num} {field} … : If set, we limit the result to a given set of keys specified in the list. the first argument must be the length of the list, and greater than zero. Non-existent keys are ignored - unless all the keys are non-existent.

  • INFIELDS {num} {field} … : If set, filter the results to ones appearing only in specific fields of the document, like title or URL. num is the number of specified field arguments

  • RETURN {num} {field} … : Use this keyword to limit which fields from the document are returned. num is the number of fields following the keyword. If num is 0, it acts like NOCONTENT .

  • SUMMARIZE … : Use this option to return only the sections of the field which contain the matched text. See Highlighting for more details

  • HIGHLIGHT … : Use this option to format occurrences of matched text. See Highlighting for more details
  • SLOP {slop} : If set, we allow a maximum of N intervening number of unmatched offsets between phrase terms. (i.e the slop for exact phrases is 0)
  • INORDER : If set, and usually used in conjunction with SLOP, we make sure the query terms appear in the same order in the document as in the query, regardless of the offsets between them.

  • LANGUAGE {language} : If set, we use a stemmer for the supplied language during search for query expansion. If querying documents in Chinese, this should be set to chinese in order to properly tokenize the query terms. Defaults to English. If an unsupported language is sent, the command returns an error. See FT.ADD for the list of languages.

  • EXPANDER {expander} : If set, we will use a custom query expander instead of the stemmer. See Extensions .

  • SCORER {scorer} : If set, we will use a custom scoring function defined by the user. See Extensions .

  • EXPLAINSCORE : If set, will return a textual description of how the scores were calculated.

  • PAYLOAD {payload} : Add an arbitrary, binary safe payload that will be exposed to custom scoring functions. See Extensions .

  • SORTBY {field} [ASC|DESC] : If specified, the results are ordered by the value of this field. This applies to both text and numeric fields.

  • LIMIT first num : If the parameters appear after the query, we limit the results to the offset and number of results given. The default is 0 10.

Note

LIMIT 0 0 can be used to count the number of documents in the resultset without actually returning them.

Complexity

O(n) for single word queries. n is the number of the results in the result set. Finding all the documents that have a specific term is O(1), however, a scan on all those documents is needed to load the documents data from redis hashes and return them.

The time complexity for more complex queries varies, but in general it’s proportional to the number of words, the number of intersection points between them and the number of results in the result set.

Returns

Array reply, where the first element is the total number of results, and then pairs of document id, and a nested array of field/value.

If NOCONTENT was given, we return an array where the first element is the total number of results, and the rest of the members are document ids.

Expiration of hashes during a search query

If a hash expiry time is reached after the start of the query process, the hash will be counted in the total number of results but name and content of the hash would not be returned.

FT.AGGREGATE

Format

  1. FT.AGGREGATE {index_name}
  2.   {query_string}
  3.   [VERBATIM]
  4.   [LOAD {nargs} {property} ...]
  5.   [GROUPBY {nargs} {property} ...
  6.     REDUCE {func} {nargs} {arg} ... [AS {name:string}]
  7.     ...
  8.   ] ...
  9.   [SORTBY {nargs} {property} [ASC|DESC] ... [MAX {num}]]
  10.   [APPLY {expr} AS {alias}] ...
  11.   [LIMIT {offset} {num}] ...
  12.   [FILTER {expr}] ...

Description

Runs a search query on an index, and performs aggregate transformations on the results, extracting statistics etc from them. See the full documentation on aggregations for further details.

Example

  1. FT.AGGREGATE idx "@url:\"about.html\""
  2.     APPLY "@timestamp - (@timestamp % 86400)" AS day
  3.     GROUPBY 2 @day @country
  4.         REDUCE count 0 AS num_visits 
  5.     SORTBY 4 @day ASC @country DESC

Parameters

  • index_name : The index the query is executed against.

  • query_string : The base filtering query that retrieves the documents. It follows the exact same syntax as the search query, including filters, unions, not, optional, etc.

  • LOAD {nargs} {property} … : Load document fields from the document HASH objects. This should be avoided as a general rule of thumb. Fields needed for aggregations should be stored as SORTABLE , where they are available to the aggregation pipeline with very low latency. LOAD hurts the performance of aggregate queries considerably, since every processed record needs to execute the equivalent of HMGET against a Redis key, which when executed over millions of keys, amounts to very high processing times.

  • GROUPBY {nargs} {property} : Group the results in the pipeline based on one or more properties. Each group should have at least one reducer (See below), a function that handles the group entries, either counting them, or performing multiple aggregate operations (see below).

    • REDUCE {func} {nargs} {arg} … [AS {name}] : Reduce the matching results in each group into a single record, using a reduction function. For example COUNT will count the number of records in the group. See the Reducers section below for more details on available reducers.

      The reducers can have their own property names using the AS {name} optional argument. If a name is not given, the resulting name will be the name of the reduce function and the group properties. For example, if a name is not given to COUNT_DISTINCT by property @foo , the resulting name will be count_distinct(@foo) .

  • SORTBY {nargs} {property} {ASC|DESC} [MAX {num}] : Sort the pipeline up until the point of SORTBY, using a list of properties. By default, sorting is ascending, but ASC or DESC can be added for each property. nargs is the number of sorting parameters, including ASC and DESC. for example: SORTBY 4 @foo ASC @bar DESC .

    MAX is used to optimized sorting, by sorting only for the n-largest elements. Although it is not connected to LIMIT , you usually need just SORTBY … MAX for common queries.

  • APPLY {expr} AS {name} : Apply a 1-to-1 transformation on one or more properties, and either store the result as a new property down the pipeline, or replace any property using this transformation. expr is an expression that can be used to perform arithmetic operations on numeric properties, or functions that can be applied on properties depending on their types (see below), or any combination thereof. For example: APPLY "sqrt(@foo)/log(@bar) + 5" AS baz will evaluate this expression dynamically for each record in the pipeline and store the result as a new property called baz, that can be referenced by further APPLY / SORTBY / GROUPBY / REDUCE operations down the pipeline.

  • LIMIT {offset} {num} . Limit the number of results to return just num results starting at index offset (zero-based). AS mentioned above, it is much more efficient to use SORTBY … MAX if you are interested in just limiting the output of a sort operation.

    However, limit can be used to limit results without sorting, or for paging the n-largest results as determined by SORTBY MAX . For example, getting results 50-100 of the top 100 results is most efficiently expressed as SORTBY 1 @foo MAX 100 LIMIT 50 50 . Removing the MAX from SORTBY will result in the pipeline sorting all the records and then paging over results 50-100.

  • FILTER {expr} . Filter the results using predicate expressions relating to values in each result. They are is applied post-query and relate to the current state of the pipeline.

Complexity

Non-deterministic. Depends on the query and aggregations performed, but it is usually linear to the number of results returned.

Returns

Array Response. Each row is an array and represents a single aggregate result.

Example output

Here we are counting GitHub events by user (actor), to produce the most active users:

  1. 127.0.0.1:6379> FT.AGGREGATE gh "*" GROUPBY 1 @actor REDUCE COUNT 0 AS num SORTBY 2 @num DESC MAX 10
  2.  1) (integer) 284784
  3.  2) 1) "actor"
  4.     2) "lombiqbot"
  5.     3) "num"
  6.     4) "22197"
  7.  3) 1) "actor"
  8.     2) "codepipeline-test"
  9.     3) "num"
  10.     4) "17746"
  11.  4) 1) "actor"
  12.     2) "direwolf-github"
  13.     3) "num"
  14.     4) "10683"
  15.  5) 1) "actor"
  16.     2) "ogate"
  17.     3) "num"
  18.     4) "6449"
  19.  6) 1) "actor"
  20.     2) "openlocalizationtest"
  21.     3) "num"
  22.     4) "4759"
  23.  7) 1) "actor"
  24.     2) "digimatic"
  25.     3) "num"
  26.     4) "3809"
  27.  8) 1) "actor"
  28.     2) "gugod"
  29.     3) "num"
  30.     4) "3512"
  31.  9) 1) "actor"
  32.     2) "xdzou"
  33.     3) "num"
  34.     4) "3216"
  35. 10) 1) "actor"
  36.     2) "opstest"
  37.     3) "num"
  38.     4) "2863"
  39. 11) 1) "actor"
  40.     2) "jikker"
  41.     3) "num"
  42.     4) "2794"
  43. (0.59s)

FT.EXPLAIN

Format

  1. FT.EXPLAIN {index} {query}

Description

Returns the execution plan for a complex query.

In the returned response, a + on a term is an indication of stemming.

Example

  1. $ redis-cli --raw
  3. 127.0.0.1:6379> FT.EXPLAIN rd "(foo bar)|(hello world) @date:[100 200]|@date:[500 +inf]"
  4. INTERSECT {
  5.   UNION {
  6.     INTERSECT {
  7.       foo
  8.       bar
  9.     }
  10.     INTERSECT {
  11.       hello
  12.       world
  13.     }
  14.   }
  15.   UNION {
  16.     NUMERIC {100.000000 <= x <= 200.000000}
  17.     NUMERIC {500.000000 <= x <= inf}
  18.   }
  19. }

Parameters

  • index : The index name. The index must be first created with FT.CREATE
  • query : The query string, as if sent to FT.SEARCH

Complexity

O(1)

Returns

String Response. A string representing the execution plan (see above example).

Tip

You should use redis-cli --raw to properly read line-breaks in the returned response.

FT.EXPLAINCLI

Format

  1. FT.EXPLAINCLI {index} {query}

Description

Returns the execution plan for a complex query but formatted for easier reading without using redis-cli --raw .

In the returned response, a + on a term is an indication of stemming.

Example

  1. $ redis-cli
  3. 127.0.0.1:6379> FT.EXPLAINCLI rd "(foo bar)|(hello world) @date:[100 200]|@date:[500 +inf]"
  4.  1) INTERSECT {
  5.  2)   UNION {
  6.  3)     INTERSECT {
  7.  4)       UNION {
  8.  5)         foo
  9.  6)         +foo(expanded)
  10.  7)       }
  11.  8)       UNION {
  12.  9)         bar
  13. 10)         +bar(expanded)
  14. 11)       }
  15. 12)     }
  16. 13)     INTERSECT {
  17. 14)       UNION {
  18. 15)         hello
  19. 16)         +hello(expanded)
  20. 17)       }
  21. 18)       UNION {
  22. 19)         world
  23. 20)         +world(expanded)
  24. 21)       }
  25. 22)     }
  26. 23)   }
  27. 24)   UNION {
  28. 25)     NUMERIC {100.000000 <= @date <= 200.000000}
  29. 26)     NUMERIC {500.000000 <= @date <= inf}
  30. 27)   }
  31. 28) }
  32. 29)

Parameters

  • index : The index name. The index must be first created with FT.CREATE
  • query : The query string, as if sent to FT.SEARCH

Complexity

O(1)

Returns

String Response. A string representing the execution plan (see above example).

Update

FT.ALTER SCHEMA ADD

Format

  1. FT.ALTER {index} SCHEMA ADD {field} {options} ...

Description

Adds a new field to the index.

Adding a field to the index will cause any future document updates to use the new field when indexing and reindexing of existing documents.

Note

Depending on how the index was created, you may be limited by the amount of additional text fields which can be added to an existing index. If the current index contains less than 32 text fields, then SCHEMA ADD will only be able to add fields up to 32 total fields (meaning that the index will only ever be able to contain 32 total text fields). If you wish for the index to contain more than 32 fields, create it with the MAXTEXTFIELDS option.

Example
  1. FT.ALTER idx SCHEMA ADD id2 NUMERIC SORTABLE

Parameters

  • index : the index name.
  • field : the field name.
  • options : the field options - refer to FT.CREATE for more information.

Complexity

O(1)

Returns

OK or an error.

Delete

FT.DROPINDEX

Format

  1. FT.DROPINDEX {index} [DD]

Description

Deletes the index.

By default, FT.DROPINDEX does not delete the document hashes associated with the index. Adding the DD option deletes the hashes as well.

Since RediSearch 2.0

Example

  1. FT.DROPINDEX idx DD

Parameters

  • index : The Fulltext index name. The index must be first created with FT.CREATE
  • DD : If set, the drop operation will delete the actual document hashes.

Returns

Status Reply: OK on success.

Alias

FT.ALIASADD

FT.ALIASUPDATE

FT.ALIASDEL

Format

  1. FT.ALIASADD {name} {index}
  2. FT.ALIASUPDATE {name} {index}
  3. FT.ALIASDEL {name}

The FT.ALIASADD and FT.ALIASDEL commands will add or remove an alias from an index. Index aliases can be used to refer to actual indexes in data commands such as FT.SEARCH or FT.ADD . This allows an administrator to transparently redirect application queries to alternative indexes.

Indexes can have more than one alias, though an alias cannot refer to another alias.

The FT.ALIASUPDATE command differs from the FT.ALIASADD command in that it will remove the alias association with a previous index, if any. FT.ALIASDD will fail, on the other hand, if the alias is already associated with another index.

Complexity

O(1)

Returns

OK or an error.

Tags

FT.TAGVALS

Format

  1. FT.TAGVALS {index} {field_name}

Description

Returns the distinct tags indexed in a Tag field .

This is useful if your tag field indexes things like cities, categories, etc.

Limitations

There is no paging or sorting, the tags are not alphabetically sorted. This command only operates on Tag fields . The strings return lower-cased and stripped of whitespaces, but otherwise unchanged.

Example

  1. FT.TAGVALS idx myTag

Parameters

  • index : The Fulltext index name. The index must be first created with FT.CREATE
  • filed_name : The name of a Tag file defined in the schema.

Returns

Array Reply: All the distinct tags in the tag index.

Complexity

O(n), n being the cardinality of the tag field.

Suggestions

FT.SUGADD

Format

  1. FT.SUGADD {key} {string} {score} [INCR] [PAYLOAD {payload}]

Description

Adds a suggestion string to an auto-complete suggestion dictionary. This is disconnected from the index definitions, and leaves creating and updating suggestions dictionaries to the user.

Example

  1. FT.SUGADD ac "hello world" 1

Parameters

  • key : the suggestion dictionary key.
  • string : the suggestion string we index
  • score : a floating point number of the suggestion string’s weight
  • INCR : if set, we increment the existing entry of the suggestion by the given score, instead of replacing the score. This is useful for updating the dictionary based on user queries in real time
  • PAYLOAD {payload} : If set, we save an extra payload with the suggestion, that can be fetched by adding the WITHPAYLOADS argument to FT.SUGGET .

Returns

Integer Reply: the current size of the suggestion dictionary.

FT.SUGGET

Format

  1. FT.SUGGET {key} {prefix} [FUZZY] [WITHSCORES] [WITHPAYLOADS] [MAX num]

Description

Gets completion suggestions for a prefix.

Example

  1. FT.SUGGET ac hell FUZZY MAX 3 WITHSCORES

Parameters

  • key : the suggestion dictionary key.
  • prefix : the prefix to complete on
  • FUZZY : if set, we do a fuzzy prefix search, including prefixes at Levenshtein distance of 1 from the prefix sent
  • MAX num : If set, we limit the results to a maximum of num (default: 5).
  • WITHSCORES : If set, we also return the score of each suggestion. this can be used to merge results from multiple instances
  • WITHPAYLOADS : If set, we return optional payloads saved along with the suggestions. If no payload is present for an entry, we return a Null Reply.

Returns

Array Reply: a list of the top suggestions matching the prefix, optionally with score after each entry

FT.SUGDEL

Format

  1. FT.SUGDEL {key} {string}

Description

Deletes a string from a suggestion index.

Example

  1. FT.SUGDEL ac "hello world"

Parameters

  • key : the suggestion dictionary key.
  • string : the string to delete

Returns

Integer Reply: 1 if the string was found and deleted, 0 otherwise.

FT.SUGLEN

Format

  1. FT.SUGLEN {key}

Description

Gets the size of an auto-complete suggestion dictionary

Example

  1. FT.SUGLEN ac

Parameters

  • key : the suggestion dictionary key.

Returns

Integer Reply: the current size of the suggestion dictionary.

Synonym

FT.SYNUPDATE

Format

  1. FT.SYNUPDATE <index name> <synonym group id> [SKIPINITIALSCAN] <term1> <term2> ...

Description

Updates a synonym group.

The command is used to create or update a synonym group with additional terms. Only documents which were indexed after the update will be affected.

Parameters

  • SKIPINITIALSCAN : If set, we do not scan and index.

FT.SYNDUMP

Format

  1. FT.SYNDUMP <index name>

Description

Dumps the contents of a synonym group.

The command is used to dump the synonyms data structure. Returns a list of synonym terms and their synonym group ids.

FT.SPELLCHECK

Format

  1.   FT.SPELLCHECK {index} {query}
  2.     [DISTANCE dist]
  3.     [TERMS {INCLUDE | EXCLUDE} {dict} [TERMS ...]]

Description

Performs spelling correction on a query, returning suggestions for misspelled terms.

See Query Spelling Correction for more details.

Parameters

  • index : the index with the indexed terms.

  • query : the search query.

  • TERMS : specifies an inclusion ( INCLUDE ) or exclusion ( EXCLUDE ) custom dictionary named {dict} . Refer to FT.DICTADD , FT.DICTDEL and FT.DICTDUMP for managing custom dictionaries.

  • DISTANCE : the maximal Levenshtein distance for spelling suggestions (default: 1, max: 4).

Returns

An array, in which each element represents a misspelled term from the query. The misspelled terms are ordered by their order of appearance in the query.

Each misspelled term, in turn, is a 3-element array consisting of the constant string “TERM”, the term itself and an array of suggestions for spelling corrections.

Each element in the spelling corrections array consists of the score of the suggestion and the suggestion itself. The suggestions array, per misspelled term, is ordered in descending order by score.

The score is calculated by dividing the number of documents in which the suggested term exists, by the total number of documents in the index. Results can be normalized by dividing scores by the highest score.

Example output

  1. 1)  1) "TERM"
  2.     2) "{term1}"
  3.     3)  1)  1)  "{score1}"
  4.             2)  "{suggestion1}"
  5.         2)  1)  "{score2}"
  6.             2)  "{suggestion2}"
  7.         .
  8.         .
  9.         .
  10. 2)  1) "TERM"
  11.     2) "{term2}"
  12.     3)  1)  1)  "{score1}"
  13.             2)  "{suggestion1}"
  14.         2)  1)  "{score2}"
  15.             2)  "{suggestion2}"
  16.         .
  17.         .
  18.         .
  19. .
  20. .
  21. .

Dictionary

FT.DICTADD

Format

  1.   FT.DICTADD {dict} {term} [{term} ...]

Description

Adds terms to a dictionary.

Parameters

  • dict : the dictionary name.

  • term : the term to add to the dictionary.

Returns

Returns int, specifically the number of new terms that were added.

FT.DICTDEL

Format

  1.   FT.DICTDEL {dict} {term} [{term} ...]

Description

Deletes terms from a dictionary.

Parameters

  • dict : the dictionary name.

  • term : the term to delete from the dictionary.

Returns

Returns int, specifically the number of terms that were deleted.

FT.DICTDUMP

Format

  1.   FT.DICTDUMP {dict}

Description

Dumps all terms in the given dictionary.

Parameters

  • dict : the dictionary name.

Returns

Returns an array, where each element is term (string).

Info

FT.INFO

Format

FT.INFO

  1. FT.INFO {index}

Description

Returns information and statistics on the index. Returned values include:

  • index_definition : reflection of FT.CREATE command parameters.
  • fields : index schema - field names, types, and attributes.
  • Number of documents.
  • Number of distinct terms.
  • Average bytes per record.
  • Size and capacity of the index buffers.
  • Indexing state and percentage as well as failures:
  • indexing : whether of not the index is being scanned in the background,
  • percent_indexed : progress of background indexing (1 if complete),
  • hash_indexing_failures : number of failures due to operations not compatible with index schema.

Optional

  • Statistics about the garbage collector for all options other than NOGC.
  • Statistics about cursors if a cursor exists for the index.
  • Statistics about stopword lists if a custom stopword list is used.
Example
  1. 127.0.0.1:6379> ft.info wik{0}
  2. 1) index_name
  3.  2) wikipedia
  4.  3) index_options
  5.  4) (empty array)
  6.  5) index_definition
  7.  6)  1) key_type
  8.      2) HASH
  9.      3) prefixes
  10.      4) 1) thing:
  11.      5) filter
  12.      6) startswith(@__key, "thing:")
  13.      7) language_field
  14.      8) __language
  15.      9) default_score
  16.     10) "1"
  17.     11) score_field
  18.     12) __score
  19.     13) payload_field
  20.     14) __payload
  21.  7) fields
  22.  8) 1) 1) title
  23.        2) type
  24.        3) TEXT
  25.        4) WEIGHT
  26.        5) "1"
  27.        6) SORTABLE
  28.     2) 1) body
  29.        2) type
  30.        3) TEXT
  31.        4) WEIGHT
  32.        5) "1"
  33.     3) 1) id
  34.        2) type
  35.        3) NUMERIC
  36.     4) 1) subject location
  37.        2) type
  38.        3) GEO
  39.  9) num_docs
  40. 10) "0"
  41. 11) max_doc_id
  42. 12) "345678"
  43. 13) num_terms
  44. 14) "691356"
  45. 15) num_records
  46. 16) "0"
  47. 17) inverted_sz_mb
  48. 18) "0"
  49. 19) total_inverted_index_blocks
  50. 20) "933290"
  51. 21) offset_vectors_sz_mb
  52. 22) "0.65932846069335938"
  53. 23) doc_table_size_mb
  54. 24) "29.893482208251953"
  55. 25) sortable_values_size_mb
  56. 26) "11.432285308837891"
  57. 27) key_table_size_mb
  58. 28) "1.239776611328125e-05"
  59. 29) records_per_doc_avg
  60. 30) "-nan"
  61. 31) bytes_per_record_avg
  62. 32) "-nan"
  63. 33) offsets_per_term_avg
  64. 34) "inf"
  65. 35) offset_bits_per_record_avg
  66. 36) "8"
  67. 37) hash_indexing_failures
  68. 38) "0"
  69. 39) indexing
  70. 40) "0"
  71. 41) percent_indexed
  72. 42) "1"
  73. 43) gc_stats
  74. 44)  1) bytes_collected
  75.      2) "4148136"
  76.      3) total_ms_run
  77.      4) "14796"
  78.      5) total_cycles
  79.      6) "1"
  80.      7) avarage_cycle_time_ms
  81.      8) "14796"
  82.      9) last_run_time_ms
  83.     10) "14796"
  84.     11) gc_numeric_trees_missed
  85.     12) "0"
  86.     13) gc_blocks_denied
  87.     14) "0"
  88. 45) cursor_stats
  89. 46) 1) global_idle
  90.     2) (integer) 0
  91.     3) global_total
  92.     4) (integer) 0
  93.     5) index_capacity
  94.     6) (integer) 128
  95.     7) index_total
  96.     8) (integer) 0
  97. 47) stopwords_list
  98. 48) 1) "tlv"
  99.     2) "summer"
  100.     3) "2020"

Parameters

  • index : The Fulltext index name. The index must be first created with FT.CREATE

Complexity

O(1)

Returns

Array Response. A nested array of keys and values.

Configuration

FT.CONFIG

Format

  1.   FT.CONFIG <GET|HELP> {option}
  2.   FT.CONFIG SET {option} {value}

Description

Retrieves, describes and sets runtime configuration options.

Parameters

  • option : the name of the configuration option, or ‘*‘ for all.
  • value : a value for the configuration option. For details about the configuration options refer to Configuring . Setting values in runtime is supported for these configuration options:
  • NOGC
  • MINPREFIX
  • MAXEXPANSIONS
  • TIMEOUT
  • ON_TIMEOUT
  • MIN_PHONETIC_TERM_LEN

Returns

When provided with a valid option name, the GET subcommand returns a string with the current option’s value. An array containing an array for each configuration option, consisting of the option’s name and current value, is returned when ‘*‘ is provided.

The SET subcommand returns ‘OK’ for valid runtime-settable option names and values.

Deprecated commands

FT.ADD

Format

  1. FT.ADD {index} {docId} {score}
  2.   [REPLACE [PARTIAL] [NOCREATE]]
  3.   [LANGUAGE {language}] 
  4.   [PAYLOAD {payload}]
  5.   [IF {condition}]
  6.   FIELDS {field} {value} [{field} {value}...]

Description

Deprecation warning

This command is deprecated and act as simpe redis HSET, the document created will be indexed only if it matches one or some indexes definitions (as defined on ft.create ), Use HSET instead.

Adds a document to the index.

Example
  1. FT.ADD idx doc1 1.0 FIELDS title "hello world"

Parameters

  • index : The Fulltext index name. The index must be first created with FT.CREATE

  • docId : The document’s id that will be returned from searches.

Notes on docId

The same docId cannot be added twice to the same index. The same docId can be added to multiple indices, but a single document with that docId is saved in the database.

  • score : The document’s rank based on the user’s ranking. This must be between 0.0 and 1.0. On v2.0 this will be translated to a ‘__score’ field in the created hash.

  • REPLACE : If set, we will do an UPSERT style insertion - and delete an older version of the document if it exists.

  • PARTIAL (only applicable with REPLACE): If set, you do not have to specify all fields for reindexing. Fields not given to the command will be loaded from the current version of the document. Also, if only non-indexable fields, score or payload are set - we do not do a full re-indexing of the document, and this will be a lot faster.

  • NOCREATE (only applicable with REPLACE): If set, the document is only updated and reindexed if it already exists. If the document does not exist, an error will be returned.

  • FIELDS : Following the FIELDS specifier, we are looking for pairs of {field} {value} to be indexed. Each field will be scored based on the index spec given in FT.CREATE . Passing fields that are not in the index spec will make them be stored as part of the document, or ignored if NOSAVE is set

  • PAYLOAD {payload} : Optionally set a binary safe payload string to the document, that can be evaluated at query time by a custom scoring function, or retrieved to the client. On v2.0 this will be translated to a ‘__payload’ field in the created hash.

  • IF {condition} : (Applicable only in conjunction with REPLACE and optionally PARTIAL ). Update the document only if a boolean expression applies to the document before the update , e.g. FT.ADD idx doc 1 REPLACE IF "@timestamp < 23323234234" .

The expression is evaluated atomically before the update, ensuring that the update will happen only if it is true.

See Aggregations for more details on the expression language.

  • LANGUAGE language : If set, we use a stemmer for the supplied language during indexing. Default to English. If an unsupported language is sent, the command returns an error. The supported languages are:

    “arabic”, “danish”, “dutch”, “english”, “finnish”, “french”, “german”, “hungarian”, “italian”, “norwegian”, “portuguese”, “romanian”, “russian”, “spanish”, “swedish”, “tamil”, “turkish” “chinese”

If indexing a Chinese language document, you must set the language to chinese in order for Chinese characters to be tokenized properly. On v2.0 this will be translated to a ‘__language’ field in the created hash.

Adding Chinese Documents

When adding Chinese-language documents, LANGUAGE chinese should be set in order for the indexer to properly tokenize the terms. If the default language is used then search terms will be extracted based on punctuation characters and whitespace. The Chinese language tokenizer makes use of a segmentation algorithm (via Friso ) which segments texts and checks it against a predefined dictionary. See Stemming for more information.

Complexity

O(n), where n is the number of tokens in the document

Returns

OK on success, or an error if something went wrong.

A special status NOADD is returned if an IF condition evaluated to false.

FT.ADD with REPLACE and PARTIAL

By default, FT.ADD does not allow updating the document, and will fail if it already exists in the index. However, updating the document is possible with the REPLACE and REPLACE PARTIAL options. REPLACE : On its own, sets the document to the new values, and reindexes it. Any fields not given will not be loaded from the current version of the document. REPLACE PARTIAL : When both arguments are used, we can update just part of the document fields, and the rest will be loaded before reindexing. Not only that, but if only the score, payload and non-indexed fields (using NOINDEX) are updated, we will not actually reindex the document, just update its metadata internally, which is a lot faster and does not create index garbage.

Overwriting other keys

FT.ADD will actually create a hash in Redis with the given fields and value. This means that if the hash already exists, it will override with the new values.

FT.DEL

Format

  1. FT.DEL {index} {doc_id} [DD]

Description

Deprecation warning

This command is deprecated and act as simpe redis DEL, the deleted document will be deleted from all the indexes it indexed on”, Use DEL instead.

Deletes a document from the index. Returns 1 if the document was in the index, or 0 if not.

since v2.0, the [DD] option is not longer support, deleting a document means to also delete the hash from redis

since v2.0, deleting a document from one index will cause this document to be deleted from all the indexes contains it

Example

  1. FT.DEL idx doc1

Parameters

  • index : The index name. The index must be first created with FT.CREATE
  • doc_id : the id of the document to be deleted. It does not actually delete the HASH key in which the document is stored. Use DEL to do that manually if needed.

Complexity

O(1)

Returns

Integer Reply: 1 if the document was deleted, 0 if not.

FT.DROP

Format

  1. FT.DROP {index} [KEEPDOCS]

Description

Deprecation warning

This command is deprecated, use FT.DROPINDEX instead.

Deletes the index and all the keys associated with it.

By default, DROP deletes the document hashes as well, but adding the KEEPDOCS option keeps the documents in place, ready for re-indexing.

If no other data is on the Redis instance, this is equivalent to FLUSHDB, apart from the fact that the index specification is not deleted.

Example

  1. FT.DROP idx KEEPDOCS

Parameters

  • index : The Fulltext index name. The index must be first created with FT.CREATE
  • KEEPDOCS : If set, the drop operation will not delete the actual document hashes.

Returns

Status Reply: OK on success.

FT.GET

Format

  1. FT.GET {index} {doc id}

Description

Deprecation warning

This command is deprecated. Use HGETALL instead.

Returns content of a document as inserted without attribute fields (score/language/payload).

If the document does not exist or is not a HASH object, we return a NULL reply

Example

  1. FT.GET idx doc1

Parameters

  • index : The index name. The index must be first created with FT.CREATE
  • documentId : The id of the document as inserted to the index

Returns

Array Reply: Key-value pairs of field names and values of the document

FT.MGET

Format

  1. FT.MGET {index} {docId} ...

Description

Deprecation warning

This command is deprecated. Use HGETALL instead.

Returns content of a document as inserted without attribute fields (score/language/payload).

In addition, it allows simpler implementation of fetching documents in clustered mode.

We return an array with exactly the same number of elements as the number of keys sent to the command.

Each element, in turn, is an array of key-value pairs representing the document.

If a document is not found or is not a valid HASH object, its place in the parent array is filled with a Null reply object.

Example

  1. FT.MGET idx doc1 doc2

Parameters

  • index : The Fulltext index name. The index must be first created with FT.CREATE
  • documentIds : The ids of the requested documents as inserted to the index

Returns

Array Reply: An array with exactly the same number of elements as the number of keys sent to the command. Each element in it is either an array representing the document or Null if it was not found.

FT.SYNADD

Deprecation warning

This command is not longer supported on versions 2.0 and above, use FT.SYNUPDATE directly.

Format

  1. FT.SYNADD <index name> <term1> <term2> ...

Description

Adds a synonym group.

The command is used to create a new synonyms group. The command returns the synonym group id which can later be used to add additional terms to that synonym group. Only documents which were indexed after the adding operation will be affected.