---
title: Query Service REST API
pubDate: 2026-08-17T09:53:44.266Z
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---
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# Query Service REST API
## [](#%5Foverview)Overview
The Query Service REST API is provided by the Query service. This API enables you to run SQL++ queries and set request-level parameters.
The API schemes and host URLs are as follows:
*
* (for secure access)
where `node` is the host name or IP address of a node running the Query service.
### [](#version-information)Version information
_Version_ : 7.2
### [](#consumes)Consumes
* `application/x-www-form-urlencoded`
* `application/json`
### [](#produces)Produces
* `application/json`
## [](#%5Fpaths)Paths
This section describes the operations available with this REST API.
**Table of Contents**
* [Query Service](#%5Fpost%5Fservice)
* [Read-Only Query Service](#%5Fget%5Fservice)
### [](#%5Fpost%5Fservice)Query Service
POST /query/service
#### [](#description)Description
Enables you to execute a SQL++ statement. This method allows you to run queries and modifying statements, and specify query parameters.
#### [](#parameters)Parameters
For POST requests, you can specify form data parameters using the `application/x-www-form-urlencoded` MIME type. Alternatively, you can specify parameters in the request body using the `application/json` MIME type with the `Content-Type` header.
| Type | Name | Description | Schema |
| -------- | ------------------------- | -------------------------------------------------- | ---------------------------------------------- |
| **Body** | **Parameters** _required_ | An object specifying one or more query parameters. | [Request Parameters](#%5Frequest%5Fparameters) |
#### [](#responses)Responses
This section describes the response HTTP status codes.
| HTTP Code | Description | Schema |
| --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------ |
| **200** | The operation was successful. | [Response Body](#%5Fresponse%5Fbody) |
| **400** | Bad Request. The request cannot be processed for one of the following reasons: The statement contains a SQL++ syntax error. The request has a missing or unrecognized HTTP parameter. The request is badly formatted (for example, the request body contains a JSON syntax error). | No Content |
| **401** | Unauthorized. The credentials provided with the request are missing or invalid. | No Content |
| **403** | Forbidden. There is a read-only violation. Either there was an attempt to create or update in a GET request or a POST request where readonly is set, or the client does not have the authorization to modify an object (index, keyspace or namespace) in the statement. | No Content |
| **404** | Not found. The statement in the request references an invalid namespace or keyspace. | No Content |
| **405** | Method not allowed. The statement in the request references an invalid namespace or keyspace. | No Content |
| **409** | Conflict. There is an attempt to create an object (keyspace or index) that already exists. | No Content |
| **410** | Gone. The server is shutting down gracefully. Previously made requests are being completed, but no new requests are being accepted. | No Content |
| **413** | Payload too large. The query is too large for the Query Service to process. | No Content |
| **500** | Internal server error. There was an unforeseen problem processing the request. | No Content |
| **503** | Service unavailable. There is an issue (that is possibly temporary) preventing the request being processed; the request queue is full or the data store is not accessible. | No Content |
#### [](#security)Security
| Type | Name |
| ---------- | ------------------------------ |
| **basic** | **[Header](#%5Fheader)** |
| **apiKey** | **[Parameter](#%5Fparameter)** |
#### [](#example-http-request)Example HTTP request
POST request with parameters as form data
Curl request
```sh
curl -v http://localhost:8093/query/service \
-d 'statement=SELECT name FROM `travel-sample`.inventory.hotel LIMIT 1' \
-u Administrator:password
```
Because it is sent as form data, the statement in this example avoids using a semicolon.
POST request with parameters in JSON format
Curl request
```sh
curl http://localhost:8093/query/service \
-H 'Content-Type: application/json' \
-d '{ "statement": "SELECT name FROM `travel-sample`.inventory.hotel LIMIT 1;" }' \
-u Administrator:password
```
Conversely, because it is sent as a JSON object, the statement in this example can contain a semicolon.
For further examples, refer to [Examples](examplesrest.md).
### [](#%5Fget%5Fservice)Read-Only Query Service
GET /query/service
#### [](#description-2)Description
Enables you to execute a SQL++ statement. This method allows you to run queries and modifying statements, and specify query parameters. It does not allow you to run modifying statements.
This endpoint is intended for situations where use of the `POST` method is restricted.
#### [](#parameters-2)Parameters
For GET requests, you specify the parameters in the query URL in URL-encoded format. For URL-encoded parameters, the format is consistent with the syntax for variables according to the RFC 6570.
For a table of parameters that can be passed in a GET request to the `/query/service` endpoint, refer to [Request Parameters](#%5Frequest%5Fparameters).
#### [](#responses-2)Responses
This section describes the response HTTP status codes.
| HTTP Code | Description | Schema |
| --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------ |
| **200** | The operation was successful. | [Response Body](#%5Fresponse%5Fbody) |
| **400** | Bad Request. The request cannot be processed for one of the following reasons: The statement contains a SQL++ syntax error. The request has a missing or unrecognized HTTP parameter. The request is badly formatted (for example, the request body contains a JSON syntax error). | No Content |
| **401** | Unauthorized. The credentials provided with the request are missing or invalid. | No Content |
| **403** | Forbidden. There is a read-only violation. Either there was an attempt to create or update in a GET request or a POST request where readonly is set, or the client does not have the authorization to modify an object (index, keyspace or namespace) in the statement. | No Content |
| **404** | Not found. The statement in the request references an invalid namespace or keyspace. | No Content |
| **405** | Method not allowed. The statement in the request references an invalid namespace or keyspace. | No Content |
| **409** | Conflict. There is an attempt to create an object (keyspace or index) that already exists. | No Content |
| **410** | Gone. The server is shutting down gracefully. Previously made requests are being completed, but no new requests are being accepted. | No Content |
| **413** | Payload too large. The query is too large for the Query Service to process. | No Content |
| **500** | Internal server error. There was an unforeseen problem processing the request. | No Content |
| **503** | Service unavailable. There is an issue (that is possibly temporary) preventing the request being processed; the request queue is full or the data store is not accessible. | No Content |
#### [](#security-2)Security
| Type | Name |
| ---------- | ------------------------------ |
| **basic** | **[Header](#%5Fheader)** |
| **apiKey** | **[Parameter](#%5Fparameter)** |
#### [](#example-http-request-2)Example HTTP request
GET request with query parameters
Curl request
```sh
curl -v http://localhost:8093/query/service?statement=SELECT%20name%20FROM%20%60travel-sample%60.inventory.hotel%20LIMIT%201%3B \
-u Administrator:password
```
For further examples, refer to [Examples](examplesrest.md).
## [](#%5Fdefinitions)Definitions
This section describes the properties consumed and returned by this REST API.
**Table of Contents**
* [Request Parameters](#%5Frequest%5Fparameters)
* [Response Body](#%5Fresponse%5Fbody)
### [](#%5Frequest%5Fparameters)Request Parameters
| Name | Description | Schema |
| ---------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------- |
| **args** _optional_ | Applicable if the statement has 1 or more positional parameters. An array of JSON values, one for each positional parameter in the statement. Note that positional parameters apply to prepared also. Refer to [Examples](examplesrest.md) for details. **Example** : \[ "LAX", 6 \] | < object > array |
| **atrcollection** _optional_ | Specifies the collection where the [active transaction record](../../learn/data/transactions.md#active-transaction-record-entries) (ATR) is stored. The collection must be present. If not specified, the ATR is stored in the default collection in the default scope in the bucket containing the first mutated document within the transaction. The value must be a string in the form "bucket.scope.collection" or "namespace:bucket.scope.collection". If any part of the path contains a special character, that part of the path must be delimited in backticks \`\`. The [node-level](admin.md#atrcollection-srv) atrcollection setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting. **Example** : "default:\`travel-sample\`.transaction.test" | string |
| **auto\_execute** _optional_ | Specifies that prepared statements should be executed automatically as soon as they are created. This saves you from having to make two separate requests in cases where you want to prepare a statement and execute it immediately. Refer to [Auto-Execute](../n1ql-language-reference/prepare.md#auto-execute) for more information. **Default** : false **Example** : true | boolean |
| **client\_context\_id** _optional_ | A piece of data supplied by the client that is echoed in the response, if present. SQL++ is agnostic about the content of this parameter; it is just echoed in the response. Maximum allowed size is 64 characters; all others will be cut. If it contains an escape character / or quote ", it will be rejected as error code 1110. | string |
| **compression** _optional_ | Compression format to use for response data on the wire. Values are case-insensitive. **Default** : "NONE" **Example** : "zip" | enum (ZIP, RLE, LZMA, LZO, NONE) |
| **controls** _optional_ | Specifies if there should be a controls section returned with the request results. When set to true, the query response document includes a controls section with runtime information provided along with the request, such as positional and named parameters or settings. If the request qualifies for caching, these values will also be cached in the completed\_requests system keyspace. The [node-level](admin.md#controls-srv) controls setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting. **Example** : true | boolean |
| **creds** _optional_ | Specifies the login credentials. The Query API supports two types of identity: local (or bucket) and admin. The format is an identity and password. You can specify credentials for multiple identities. If credentials are supplied in the request header, then HTTP Basic Authentication takes precedence and creds is ignored. **Example** : \[ { "user" : "local:bucket-name", "pass" : "password" }, { "user" : "admin:admin-name", "pass" : "password" } \] | < [Credentials](#%5Fcredentials) \> array |
| **durability\_level** _optional_ | The level of [durability](../../learn/data/durability.md) for mutations produced by the request. If the request contains a BEGIN TRANSACTION statement, or a DML statement with the [tximplicit](#tximplicit) parameter set to true, the durability level is specified for all mutations within that transaction. Durability is also supported for non-transactional DML statements. In this case, the kvtimeout parameter is used as the durability timeout. If not specified, the default durability level is "majority". Set the durability level to "none" or "" to specify no durability. **Default** : "majority" **Example** : "none" | enum ("", none, majority, majorityAndPersistActive, persistToMajority) |
| **encoded\_plan** _optional_ | In Couchbase Server 6.5 and later, this parameter is ignored and has no effect. It is included for compatibility with previous versions of Couchbase Server. | string |
| **encoding** _optional_ | Desired character encoding for the query results. Only possible value is UTF-8 and is case-insensitive. **Default** : "UTF-8" | string |
| **format** _optional_ | Desired format for the query results. Values are case-insensitive. **Default** : "JSON" **Example** : "XML" | enum (JSON, XML, CSV, TSV) |
| **kvtimeout** _optional_ | The maximum time to wait for a KV operation before timing out. Only applies to statements within a transaction, or to non-transactional statements when the durability\_level is set. The value for this parameter is a string. Its format includes an amount and a mandatory unit, e.g. 10ms (10 milliseconds) or 0.5s (half a second). Valid units are: ns (nanoseconds) us (microseconds) ms (milliseconds) s (seconds) m (minutes) h (hours) Specify a duration of 0 or a negative duration to disable. When disabled, no timeout is applied and the KV operation runs for however long it takes. **Default** : "2.5s" **Example** : "10ms" | string |
| **max\_parallelism** _optional_ | Specifies the maximum parallelism for the query. The [node-level](admin.md#max-parallelism-srv) max-parallelism setting specifies the ceiling for this parameter for a single node. If the request-level parameter is zero or negative, the parallelism for the query is set to the node-level setting. If the request-level parameter is greater than zero and less than the node-level setting, the request-level parameter overrides the node-level setting. If the request-level parameter is greater than the node-level setting, the parallelism for the query is set to the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryMaxParallelism) queryMaxParallelism setting specifies the ceiling for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. To enable queries to run in parallel, you must specify the cluster-level queryMaxParallelism parameter, or specify the node-level max-parallelism parameter on all Query nodes. The default value is the same as the number of partitions of the index selected for the query. **Example** : 3 | integer (int32) |
| **memory\_quota** _optional_ | Specifies the maximum amount of memory the request may use, in MB. Specify 0 (the default value) to disable. When disabled, there is no quota. This parameter enforces a ceiling on the memory used for the tracked documents required for processing a request. It does not take into account any other memory that might be used to process a request, such as the stack, the operators, or some intermediate values. Within a transaction, this setting enforces the memory quota for the transaction by tracking the delta table and the transaction log (approximately). The [node-level](admin.md#memory-quota-srv) memory-quota setting specifies the ceiling for this parameter for a single node. If the node-level setting is zero (the default), the request-level parameter overrides the node-level setting. If the node-level setting is greater than zero, the request-level parameter is capped by the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryMemoryQuota) queryMemoryQuota setting specifies the ceiling for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. **Default** : 0 **Example** : 4 | integer (int32) |
| **metrics** _optional_ | Specifies that metrics should be returned with query results. **Default** : true **Example** : false | boolean |
| **namespace** _optional_ | Specifies the namespace to use. Currently, only the default namespace is available. **Example** : "default" | string |
| **numatrs** _optional_ | Reserved for future use. This parameter is ignored and has no effect. | integer (int32) |
| **pipeline\_batch** _optional_ | Controls the number of items execution operators can batch for Fetch from the KV. The [node-level](admin.md#pipeline-batch-srv) pipeline-batch setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting, but only if it is lower than the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryPipelineBatch) queryPipelineBatch setting specifies the default for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. **Example** : 64 | integer (int32) |
| **pipeline\_cap** _optional_ | Maximum number of items each execution operator can buffer between various operators. The [node-level](admin.md#pipeline-cap-srv) pipeline-cap setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting, but only if it is lower than the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryPipelineCap) queryPipelineCap setting specifies the default for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. **Example** : 1024 | integer (int32) |
| **prepared** _optional_ | _Required_ if statement not provided. The name of the prepared SQL++ statement to be executed. Refer to [EXECUTE](../n1ql-language-reference/execute.md) for examples. If both prepared and statement are present and non-empty, an error is returned. **Example** : "\[127.0.0.1:8091\]pricy\_hotel" | string |
| **preserve\_expiry** _optional_ | Specifies whether documents should keep their current expiration setting when modified by a DML statement. If true, documents will keep any existing expiration setting when modified by a DML statement. If the DML statement explicitly specifies the document expiration, the statement overrides this parameter, and the expiration is changed. If false, document expiration is set to 0 when modified by a DML statement, unless the DML statement explicitly specifies the document expiration. Not supported for statements in a transaction. **Default** : false **Example** : true | boolean |
| **pretty** _optional_ | Specifies the query results returned in pretty format. The [node-level](admin.md#pretty-srv) pretty setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting. **Example** : false | boolean |
| **profile** _optional_ | Specifies if there should be a profile section returned with the request results. The valid values are: off No profiling information is added to the query response. phases The query response includes a profile section with stats and details about various phases of the query plan and execution. Three phase times will be included in the system:active\_requests and system:completed\_requests monitoring keyspaces. timings Besides the phase times, the profile section of the query response document will include a full query plan with timing and information about the number of processed documents at each phase. This information will be included in the system:active\_requests and system:completed\_requests keyspaces. If profile is not set as one of the above values, then the profile setting does not change. The [node-level](admin.md#profile-srv) profile setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting. **Example** : "phases" | enum (off, phases, timings) |
| **query\_context** _optional_ | Specifies the namespace, bucket, and scope used to resolve partial keyspace references within the request. The query context may be a _full path_, containing namespace, bucket, and scope; or a _relative path_, containing just the bucket and scope. Currently, only the default namespace is available. If the namespace name is omitted, the default namespace in the current session is used. **Default** : "default:" **Example** : "default:travel-sample.inventory" | string |
| **readonly** _optional_ | Controls whether a query can change a resulting recordset. If readonly is true, then the following statements are not allowed: CREATE INDEX DROP INDEX INSERT MERGE UPDATE UPSERT When using GET requests, it's best to set readonly to true. **Default** : false **Example** : true | boolean |
| **scan\_cap** _optional_ | Maximum buffered channel size between the indexer client and the query service for index scans. This parameter controls when to use scan backfill. Use 0 or a negative number to disable. Smaller values reduce GC, while larger values reduce indexer backfill. The [node-level](admin.md#scan-cap-srv) scan-cap setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting, but only if it is lower than the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryScanCap) queryScanCap setting specifies the default for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. **Example** : 1024 | integer (int32) |
| **scan\_consistency** _optional_ | Specifies the consistency guarantee or constraint for index scanning. The valid values are: not\_bounded No timestamp vector is used in the index scan. This is the fastest mode, because it avoids the costs of obtaining the vector and waiting for the index to catch up to the vector. at\_plus This implements bounded consistency. The request includes a scan\_vector parameter and value, which is used as a lower bound. This can be used to implement read-your-own-writes (RYOW). request\_plus This implements strong consistency per request. Before processing the request, a current vector is obtained. The vector is used as a lower bound for the statements in the request. If there are DML statements in the request, RYOW is also applied within the request. If request\_plus is specified in a query that runs during a failover of an index node, the query waits until the rebalance operation completes and the index data has rebalanced before returning a result. statement\_plus This implements strong consistency per statement. Before processing each statement, a current vector is obtained and used as a lower bound for that statement. Values are case-insensitive. For multi-statement requests, the default behavior is RYOW within each request. If you want to disable RYOW within a request, add a separate request\_consistency parameter that can be set to not\_bounded. If the request contains a BEGIN TRANSACTION statement, or a DML statement with the [tximplicit](#tximplicit) parameter set to true, then this parameter sets the transactional scan consistency. Refer to [Transactional Scan Consistency](../../settings/query-settings.md#transactional-scan-consistency) for details. **Default** : "not\_bounded" **Example** : "at\_plus" | enum (not\_bounded, at\_plus, request\_plus, statement\_plus) |
| **scan\_vector** _optional_ | _Required_ if scan\_consistency is at\_plus and scan\_vectors not provided. Specify the lower bound vector timestamp for one keyspace when using at\_plus scan consistency. Scan vectors are built of two-element \[value, guard\] entries: value: a vBucket's sequence number (a JSON number) guard: a vBucket's UUID (a string) Scan vectors have two forms: **Full scan vector**: an array of \[value, guard\] entries, giving an entry for every vBucket in the system. **Sparse scan vectors**: an object providing entries for specific vBuckets, mapping a vBucket number (a string) to each \[value, guard\] entry. Note that scan\_vector can only be used if the query uses at most one keyspace; if it is used for a query referencing more than one keyspace, the query will fail with an error. For queries referencing multiple keyspaces, use scan\_vectors. **Example** : { "5" : \[ 5409393, "VB5ID" \], "19" : \[ 47574574, "VB19ID" \] } | object |
| **scan\_vectors** _optional_ | _Required_ if scan\_consistency is at\_plus and scan\_vector not provided. A map from keyspace names to scan vectors. See scan\_vector. The scan vectors can be Full or Sparse. | object |
| **scan\_wait** _optional_ | Can be supplied with scan\_consistency values of request\_plus, statement\_plus and at\_plus. Specifies the maximum time the client is willing to wait for an index to catch up to the vector timestamp in the request. Specifies how much time the client is willing to wait for the indexer to satisfy the required scan\_consistency and scan\_vector criteria. After receiving the scan request, if the indexer is unable to catch up within the scan\_wait time and initiate the scan, the indexer aborts with an error and the scan fails. Its format includes an amount and a mandatory unit, e.g. 10ms (10 milliseconds) or 0.5s (half a second). Valid units are: ns (nanoseconds) us (microseconds) ms (milliseconds) s (seconds) m (minutes) h (hours) Specify 0 or a negative integer to disable. **Default** : "" **Example** : "30m" | string (duration) |
| **signature** _optional_ | Include a header for the results schema in the response. **Default** : true **Example** : false | boolean |
| **statement** _optional_ | _Required_ if prepared not provided. Any valid SQL++ statement for a POST request, or a read-only SQL++ statement (SELECT, EXPLAIN) for a GET request. If both prepared and statement are present and non-empty, an error is returned. When specifying the request parameters as form data, the statement may not contain an unescaped semicolon (;). If it does, the Query Service responds with error 1040\. To avoid this, either URL-encode the semicolon as %3B, or just omit the semicolon if possible. This restriction does not apply when specifying the request parameters in JSON format. **Example** : "SELECT \* FROM \`travel-sample\`.inventory.hotel LIMIT 1" | string |
| **timeout** _optional_ | Maximum time to spend on the request before timing out. The value for this parameter is a string. Its format includes an amount and a mandatory unit, e.g. 10ms (10 milliseconds) or 0.5s (half a second). Valid units are: ns (nanoseconds) us (microseconds) ms (milliseconds) s (seconds) m (minutes) h (hours) Specify a duration of 0 or a negative duration to disable. When disabled, no timeout is applied and the request runs for however long it takes. If [txid](#txid) or [tximplicit](#tximplicit) is set, this parameter is ignored. The request inherits the remaining time of the transaction as timeout. The [node-level](admin.md#timeout-srv) timeout setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting. However, if the node-level setting is greater than 0, the timeout for the query is limited to the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryTimeout) queryTimeout setting specifies the default for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. **Example** : "30m" | string (duration) |
| **txdata** _optional_ | Transaction data. For internal use only. | object |
| **txid** _optional_ | _Required_ for statements within a transaction. Transaction ID. Specifies the transaction to which a statement belongs. For use with DML statements within a transaction, rollbacks, and commits. The transaction ID should be the same as the transaction ID generated by the BEGIN TRANSACTION statement. The transaction must be active and non-expired. **Example** : "d81d9b4a-b758-4f98-b007-87ba262d3a51" | string (UUID) |
| **tximplicit** _optional_ | Specifies that a DML statement is a singleton transaction. When this parameter is true, the Query service starts a transaction and executes the statement. If execution is successful, the Query service commits the transaction; otherwise the transaction is rolled back. The statement may not be part of an ongoing transaction. If the [txid](#txid) request-level parameter is set, the tximplicit parameter is ignored. **Default** : false **Example** : true | boolean |
| **txstmtnum** _optional_ | Transaction statement number. The transaction statement number must be a positive integer, and must be higher than any previous transaction statement numbers in the transaction. If the transaction statement number is lower than the transaction statement number for any previous statement, an error is generated. **Example** : 10 | integer (int32) |
| **txtimeout** _optional_ | Maximum time to spend on a transaction before timing out. Only applies to BEGIN TRANSACTION statements, or DML statements for which [tximplicit](#tximplicit) is set. For other statements, it is ignored. Within a transaction, the request-level [timeout](#timeout%5Freq) parameter is ignored. The transaction timeout clock starts when the BEGIN WORK statement is successful. Once the transaction timeout is reached, no statement is allowed to continue in the transaction. The value for this parameter is a string. Its format includes an amount and a mandatory unit, e.g. 10ms (10 milliseconds) or 0.5s (half a second). Valid units are: ns (nanoseconds) us (microseconds) ms (milliseconds) s (seconds) m (minutes) h (hours) Specify a duration of 0 to disable. When disabled, the request-level timeout is set to the default. The [node-level](admin.md#txtimeout-srv) txtimeout setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting. However, if the node-level setting is greater than 0, the transaction timeout for the query is limited to the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryTxTimeout) queryTxTimeout setting specifies the default for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. The default is "15s" for cbq files or scripts, "2m" for interactive cbq sessions or redirected input. **Example** : "30m" | string (duration) |
| **use\_cbo** _optional_ | Specifies whether the cost-based optimizer is enabled. The [node-level](admin.md#use-cbo-srv) use-cbo setting specifies the default for this parameter for a single node. The request-level parameter overrides the node-level setting. In addition, the [cluster-level](../../rest-api/rest-cluster-query-settings.md#queryUseCBO) queryUseCBO setting specifies the default for this parameter for the whole cluster. When you change the cluster-level setting, the node-level setting is overwritten for all nodes in the cluster. **Example** : true | boolean |
| **use\_fts** _optional_ | [ENTERPRISE EDITION](https://www.couchbase.com/products/editions) Specifies that the query should use a full-text index. If the query contains a USING FTS hint, that takes priority over this parameter. If the query does not contain a USING FTS hint, and this parameter is set to true, all full-text indexes are considered for the query. If a qualified full-text index is available, it is selected for the query. If none of the available full-text indexes are qualified, the available GSI indexes are considered instead. Refer to [Flex Indexes](../n1ql-language-reference/flex-indexes.md) for more information. **Default** : false **Example** : true | boolean |
| **$** _optional_ | Applicable if the statement has 1 or more named parameters. The name of a named parameter consists of two parts: The $ character An identifier that starts with an alpha character followed by one or more alphanumeric characters. The value of the named parameter is any JSON value. Named parameters apply to prepared also. Refer to [Examples](examplesrest.md) for details. | string (any JSON value) |
### [](#%5Fcredentials)Credentials
| Name | Description | Schema |
| ------------------- | -------------------------------------------------------------------------------------------------------------------------------- | ------ |
| **user** _optional_ | An identity for authentication. Note that bucket names may be prefixed with local:, and admin names may be prefixed with admin:. | string |
| **pass** _optional_ | A password for authentication. | string |
### [](#%5Fresponse%5Fbody)Response Body
The response body has the following structure.
| Name | Description | Schema |
| ------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| **requestID** _optional_ | A unique identifier for the response. | string (UUID) |
| **clientContextID** _optional_ | The client context ID of the request, if one was supplied — see client\_context\_id in [Request Parameters](#%5Frequest%5Fparameters). | string |
| **signature** _optional_ | The schema of the results. Present only when the query completes successfully. **Example** : { "id" : "json" } | object |
| **results** _optional_ | An array of all the objects returned by the query. An object can be any JSON value. | < object > array |
| **status** _optional_ | The status of the request. | enum (success, running, errors, completed, stopped, timeout, fatal) |
| **errors** _optional_ | An array of 0 or more error objects. If an error occurred during processing of the request, it will be represented by an error object in this list. | < [Conditions](#%5Fconditions) \> array |
| **warnings** _optional_ | An array of 0 or more warning objects. If a warning occurred during processing of the request, it is represented by a warning object in this list. | < [Conditions](#%5Fconditions) \> array |
| **metrics** _optional_ | An object containing metrics about the request. | [Metrics](#%5Fmetrics) |
| **controls** _optional_ | An object containing runtime information provided along with the request. Present only if controls was set to true in the [Request Parameters](#%5Frequest%5Fparameters). | [Controls](#%5Fcontrols) |
### [](#%5Fconditions)Conditions
Errors and warnings have the following format.
| Name | Description | Schema |
| ------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- |
| **code** _required_ | A unique number that identifies the error or warning. The code ranges are partitioned by component. The codes can also include parts that indicate severity and transience. This property is always present in every condition returned in the Query REST API or captured in a log. | integer |
| **msg** _required_ | A message describing the error or warning in detail. This property is always present in every condition returned in the Query REST API or captured in a log. | string |
| **name** _optional_ | Unique name that has a 1:1 mapping to the code. Uniquely identifies the condition. This property is helpful for pattern matching and can have meaning, making it more memorable than the code. The name should be fully qualified. **Example** : "indexing.scan.io\_failure" | string |
| **sev** _optional_ | One of the following SQL++ severity levels, listed in order of severity: Severe Error Warn Info | integer |
| **temp** _optional_ | Indicates if the condition is transient — for example, the queue is full. If the value is false, it tells clients and users that a retry without modification produces the same condition. | boolean |
Additional elements not listed here might also be present. Clients and consumers of the REST API or the logs must accommodate any additional elements.
### [](#%5Fmetrics)Metrics
| Name | Description | Schema |
| ---------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------ |
| **elapsedTime** _required_ | The total time taken for the request, that is the time from when the request was received until the results were returned. | string |
| **executionTime** _required_ | The time taken for the execution of the request, that is the time from when query execution started until the results were returned. | string |
| **resultCount** _required_ | The total number of objects in the results. | integer (unsigned) |
| **resultSize** _required_ | The total number of bytes in the results. | integer (unsigned) |
| **mutationCount** _optional_ | The number of mutations that were made during the request. | integer (unsigned) |
| **sortCount** _optional_ | The number of objects that were sorted. Present only if the request includes ORDER BY. If a query includes ORDER BY, LIMIT, or OFFSET clauses, an application can use the sortCount value to give the overall number of results in a message such as "page 1 of N". | integer (unsigned) |
| **usedMemory** _optional_ | The amount of document memory used to execute the request. This property is only returned if a memory quota was set for the query. | integer (unsigned) |
| **errorCount** _optional_ | The number of errors that occurred during the request. | integer (unsigned) |
| **warningCount** _optional_ | The number of warnings that occurred during the request. | integer (unsigned) |
Additional elements not listed here might also be present. Clients and consumers of the REST API or the logs must accommodate any additional elements.
### [](#%5Fcontrols)Controls
| Name | Description | Schema |
| -------------------------------- | ---------------------------------------------------------------------------------------------------------------- | ------------------ |
| **scan\_consistency** _optional_ | The value of the query setting Scan Consistency used for the query. | string |
| **use\_cbo** _optional_ | Whether the cost-based optimizer was enabled for the query. | boolean |
| **memoryQuota** _optional_ | The memory quota for the request, in MB. This property is only returned if a memory quota was set for the query. | integer (unsigned) |
| **stmtType** _optional_ | The type of query statement. **Example** : "SELECT" | string |
Additional elements not listed here might also be present. Clients and consumers of the REST API or the logs must accommodate any additional elements.
## [](#%5Fsecurityscheme)Security
The Query Service API accepts credentials via HTTP basic authentication header, or via the `creds` request parameter. If a request contains both HTTP basic authentication header and a `creds` parameter, the `creds` parameter is ignored and only the HTTP basic authentication header is used for authenticating.
### [](#%5Fheader)Header
Specify a user name and password via HTTP headers. This method can only be used to provide a single credential.
_Type_ : basic
### [](#%5Fparameter)Parameter
Specify user names and passwords via the `creds` request parameter. This is the only method that can provide multiple credentials for a request.
_Type_ : apiKey
_Name_ : creds
_In_ : QUERY
### [](#rbac-role)RBAC Role
Users must have the relevant _Administrative_ or _Query & Index_ RBAC roles, depending on the types of query they intend to run. In addition, users must have permissions on the required buckets, scopes, and collections, where appropriate. Refer to [Roles](../../learn/security/roles.md) for more details.