{-# LANGUAGE DeriveDataTypeable #-} {-# LANGUAGE DeriveGeneric #-} {-# LANGUAGE OverloadedStrings #-} {-# LANGUAGE RecordWildCards #-} {-# LANGUAGE TypeFamilies #-} {-# OPTIONS_GHC -fno-warn-unused-imports #-} {-# OPTIONS_GHC -fno-warn-unused-binds #-} {-# OPTIONS_GHC -fno-warn-unused-matches #-} -- Derived from AWS service descriptions, licensed under Apache 2.0. -- | -- Module : Network.AWS.DynamoDB.Query -- Copyright : (c) 2013-2016 Brendan Hay -- License : Mozilla Public License, v. 2.0. -- Maintainer : Brendan Hay -- Stability : auto-generated -- Portability : non-portable (GHC extensions) -- -- A /Query/ operation uses the primary key of a table or a secondary index to directly access items from that table or index. -- -- Use the /KeyConditionExpression/ parameter to provide a specific value for the partition key. The /Query/ operation will return all of the items from the table or index with that partition key value. You can optionally narrow the scope of the /Query/ operation by specifying a sort key value and a comparison operator in /KeyConditionExpression/. You can use the /ScanIndexForward/ parameter to get results in forward or reverse order, by sort key. -- -- Queries that do not return results consume the minimum number of read capacity units for that type of read operation. -- -- If the total number of items meeting the query criteria exceeds the result set size limit of 1 MB, the query stops and results are returned to the user with the /LastEvaluatedKey/ element to continue the query in a subsequent operation. Unlike a /Scan/ operation, a /Query/ operation never returns both an empty result set and a /LastEvaluatedKey/ value. /LastEvaluatedKey/ is only provided if the results exceed 1 MB, or if you have used the /Limit/ parameter. -- -- You can query a table, a local secondary index, or a global secondary index. For a query on a table or on a local secondary index, you can set the /ConsistentRead/ parameter to 'true' and obtain a strongly consistent result. Global secondary indexes support eventually consistent reads only, so do not specify /ConsistentRead/ when querying a global secondary index. -- -- This operation returns paginated results. module Network.AWS.DynamoDB.Query ( -- * Creating a Request query , Query -- * Request Lenses , qKeyConditions , qProjectionExpression , qAttributesToGet , qExpressionAttributeNames , qFilterExpression , qQueryFilter , qConsistentRead , qExpressionAttributeValues , qReturnConsumedCapacity , qScanIndexForward , qLimit , qSelect , qKeyConditionExpression , qConditionalOperator , qExclusiveStartKey , qIndexName , qTableName -- * Destructuring the Response , queryResponse , QueryResponse -- * Response Lenses , qrsLastEvaluatedKey , qrsCount , qrsScannedCount , qrsItems , qrsConsumedCapacity , qrsResponseStatus ) where import Network.AWS.DynamoDB.Types import Network.AWS.DynamoDB.Types.Product import Network.AWS.Lens import Network.AWS.Pager import Network.AWS.Prelude import Network.AWS.Request import Network.AWS.Response -- | Represents the input of a /Query/ operation. -- -- /See:/ 'query' smart constructor. data Query = Query' { _qKeyConditions :: !(Maybe (Map Text Condition)) , _qProjectionExpression :: !(Maybe Text) , _qAttributesToGet :: !(Maybe (List1 Text)) , _qExpressionAttributeNames :: !(Maybe (Map Text Text)) , _qFilterExpression :: !(Maybe Text) , _qQueryFilter :: !(Maybe (Map Text Condition)) , _qConsistentRead :: !(Maybe Bool) , _qExpressionAttributeValues :: !(Maybe (Map Text AttributeValue)) , _qReturnConsumedCapacity :: !(Maybe ReturnConsumedCapacity) , _qScanIndexForward :: !(Maybe Bool) , _qLimit :: !(Maybe Nat) , _qSelect :: !(Maybe Select) , _qKeyConditionExpression :: !(Maybe Text) , _qConditionalOperator :: !(Maybe ConditionalOperator) , _qExclusiveStartKey :: !(Maybe (Map Text AttributeValue)) , _qIndexName :: !(Maybe Text) , _qTableName :: !Text } deriving (Eq,Read,Show,Data,Typeable,Generic) -- | Creates a value of 'Query' with the minimum fields required to make a request. -- -- Use one of the following lenses to modify other fields as desired: -- -- * 'qKeyConditions' -- -- * 'qProjectionExpression' -- -- * 'qAttributesToGet' -- -- * 'qExpressionAttributeNames' -- -- * 'qFilterExpression' -- -- * 'qQueryFilter' -- -- * 'qConsistentRead' -- -- * 'qExpressionAttributeValues' -- -- * 'qReturnConsumedCapacity' -- -- * 'qScanIndexForward' -- -- * 'qLimit' -- -- * 'qSelect' -- -- * 'qKeyConditionExpression' -- -- * 'qConditionalOperator' -- -- * 'qExclusiveStartKey' -- -- * 'qIndexName' -- -- * 'qTableName' query :: Text -- ^ 'qTableName' -> Query query pTableName_ = Query' { _qKeyConditions = Nothing , _qProjectionExpression = Nothing , _qAttributesToGet = Nothing , _qExpressionAttributeNames = Nothing , _qFilterExpression = Nothing , _qQueryFilter = Nothing , _qConsistentRead = Nothing , _qExpressionAttributeValues = Nothing , _qReturnConsumedCapacity = Nothing , _qScanIndexForward = Nothing , _qLimit = Nothing , _qSelect = Nothing , _qKeyConditionExpression = Nothing , _qConditionalOperator = Nothing , _qExclusiveStartKey = Nothing , _qIndexName = Nothing , _qTableName = pTableName_ } -- | This is a legacy parameter, for backward compatibility. New applications should use /KeyConditionExpression/ instead. Do not combine legacy parameters and expression parameters in a single API call; otherwise, DynamoDB will return a /ValidationException/ exception. -- -- The selection criteria for the query. For a query on a table, you can have conditions only on the table primary key attributes. You must provide the partition key name and value as an 'EQ' condition. You can optionally provide a second condition, referring to the sort key. -- -- If you don\'t provide a sort key condition, all of the items that match the partition key will be retrieved. If a /FilterExpression/ or /QueryFilter/ is present, it will be applied after the items are retrieved. -- -- For a query on an index, you can have conditions only on the index key attributes. You must provide the index partition key name and value as an 'EQ' condition. You can optionally provide a second condition, referring to the index sort key. -- -- Each /KeyConditions/ element consists of an attribute name to compare, along with the following: -- -- - /AttributeValueList/ - One or more values to evaluate against the supplied attribute. The number of values in the list depends on the /ComparisonOperator/ being used. -- -- For type Number, value comparisons are numeric. -- -- String value comparisons for greater than, equals, or less than are based on ASCII character code values. For example, 'a' is greater than 'A', and 'a' is greater than 'B'. For a list of code values, see . -- -- For Binary, DynamoDB treats each byte of the binary data as unsigned when it compares binary values. -- -- - /ComparisonOperator/ - A comparator for evaluating attributes, for example, equals, greater than, less than, and so on. -- -- For /KeyConditions/, only the following comparison operators are supported: -- -- 'EQ | LE | LT | GE | GT | BEGINS_WITH | BETWEEN' -- -- The following are descriptions of these comparison operators. -- -- - 'EQ' : Equal. -- -- /AttributeValueList/ can contain only one /AttributeValue/ of type String, Number, or Binary (not a set type). If an item contains an /AttributeValue/ element of a different type than the one specified in the request, the value does not match. For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. Also, '{\"N\":\"6\"}' does not equal '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'LE' : Less than or equal. -- -- /AttributeValueList/ can contain only one /AttributeValue/ element of type String, Number, or Binary (not a set type). If an item contains an /AttributeValue/ element of a different type than the one provided in the request, the value does not match. For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. Also, '{\"N\":\"6\"}' does not compare to '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'LT' : Less than. -- -- /AttributeValueList/ can contain only one /AttributeValue/ of type String, Number, or Binary (not a set type). If an item contains an /AttributeValue/ element of a different type than the one provided in the request, the value does not match. For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. Also, '{\"N\":\"6\"}' does not compare to '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'GE' : Greater than or equal. -- -- /AttributeValueList/ can contain only one /AttributeValue/ element of type String, Number, or Binary (not a set type). If an item contains an /AttributeValue/ element of a different type than the one provided in the request, the value does not match. For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. Also, '{\"N\":\"6\"}' does not compare to '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'GT' : Greater than. -- -- /AttributeValueList/ can contain only one /AttributeValue/ element of type String, Number, or Binary (not a set type). If an item contains an /AttributeValue/ element of a different type than the one provided in the request, the value does not match. For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. Also, '{\"N\":\"6\"}' does not compare to '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'BEGINS_WITH' : Checks for a prefix. -- -- /AttributeValueList/ can contain only one /AttributeValue/ of type String or Binary (not a Number or a set type). The target attribute of the comparison must be of type String or Binary (not a Number or a set type). -- -- - 'BETWEEN' : Greater than or equal to the first value, and less than or equal to the second value. -- -- /AttributeValueList/ must contain two /AttributeValue/ elements of the same type, either String, Number, or Binary (not a set type). A target attribute matches if the target value is greater than, or equal to, the first element and less than, or equal to, the second element. If an item contains an /AttributeValue/ element of a different type than the one provided in the request, the value does not match. For example, '{\"S\":\"6\"}' does not compare to '{\"N\":\"6\"}'. Also, '{\"N\":\"6\"}' does not compare to '{\"NS\":[\"6\", \"2\", \"1\"]}' -- -- For usage examples of /AttributeValueList/ and /ComparisonOperator/, see in the /Amazon DynamoDB Developer Guide/. qKeyConditions :: Lens' Query (HashMap Text Condition) qKeyConditions = lens _qKeyConditions (\ s a -> s{_qKeyConditions = a}) . _Default . _Map; -- | A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, sets, or elements of a JSON document. The attributes in the expression must be separated by commas. -- -- If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result. -- -- For more information, see in the /Amazon DynamoDB Developer Guide/. -- -- /ProjectionExpression/ replaces the legacy /AttributesToGet/ parameter. qProjectionExpression :: Lens' Query (Maybe Text) qProjectionExpression = lens _qProjectionExpression (\ s a -> s{_qProjectionExpression = a}); -- | This is a legacy parameter, for backward compatibility. New applications should use /ProjectionExpression/ instead. Do not combine legacy parameters and expression parameters in a single API call; otherwise, DynamoDB will return a /ValidationException/ exception. -- -- This parameter allows you to retrieve attributes of type List or Map; however, it cannot retrieve individual elements within a List or a Map. -- -- The names of one or more attributes to retrieve. If no attribute names are provided, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result. -- -- Note that /AttributesToGet/ has no effect on provisioned throughput consumption. DynamoDB determines capacity units consumed based on item size, not on the amount of data that is returned to an application. -- -- You cannot use both /AttributesToGet/ and /Select/ together in a /Query/ request, /unless/ the value for /Select/ is 'SPECIFIC_ATTRIBUTES'. (This usage is equivalent to specifying /AttributesToGet/ without any value for /Select/.) -- -- If you query a local secondary index and request only attributes that are projected into that index, the operation will read only the index and not the table. If any of the requested attributes are not projected into the local secondary index, DynamoDB will fetch each of these attributes from the parent table. This extra fetching incurs additional throughput cost and latency. -- -- If you query a global secondary index, you can only request attributes that are projected into the index. Global secondary index queries cannot fetch attributes from the parent table. qAttributesToGet :: Lens' Query (Maybe (NonEmpty Text)) qAttributesToGet = lens _qAttributesToGet (\ s a -> s{_qAttributesToGet = a}) . mapping _List1; -- | One or more substitution tokens for attribute names in an expression. The following are some use cases for using /ExpressionAttributeNames/: -- -- - To access an attribute whose name conflicts with a DynamoDB reserved word. -- -- - To create a placeholder for repeating occurrences of an attribute name in an expression. -- -- - To prevent special characters in an attribute name from being misinterpreted in an expression. -- -- Use the __#__ character in an expression to dereference an attribute name. For example, consider the following attribute name: -- -- - 'Percentile' -- -- The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For the complete list of reserved words, see in the /Amazon DynamoDB Developer Guide/). To work around this, you could specify the following for /ExpressionAttributeNames/: -- -- - '{\"#P\":\"Percentile\"}' -- -- You could then use this substitution in an expression, as in this example: -- -- - '#P = :val' -- -- Tokens that begin with the __:__ character are /expression attribute values/, which are placeholders for the actual value at runtime. -- -- For more information on expression attribute names, see in the /Amazon DynamoDB Developer Guide/. qExpressionAttributeNames :: Lens' Query (HashMap Text Text) qExpressionAttributeNames = lens _qExpressionAttributeNames (\ s a -> s{_qExpressionAttributeNames = a}) . _Default . _Map; -- | A string that contains conditions that DynamoDB applies after the /Query/ operation, but before the data is returned to you. Items that do not satisfy the /FilterExpression/ criteria are not returned. -- -- A /FilterExpression/ is applied after the items have already been read; the process of filtering does not consume any additional read capacity units. -- -- For more information, see in the /Amazon DynamoDB Developer Guide/. -- -- /FilterExpression/ replaces the legacy /QueryFilter/ and /ConditionalOperator/ parameters. qFilterExpression :: Lens' Query (Maybe Text) qFilterExpression = lens _qFilterExpression (\ s a -> s{_qFilterExpression = a}); -- | This is a legacy parameter, for backward compatibility. New applications should use /FilterExpression/ instead. Do not combine legacy parameters and expression parameters in a single API call; otherwise, DynamoDB will return a /ValidationException/ exception. -- -- A condition that evaluates the query results after the items are read and returns only the desired values. -- -- This parameter does not support attributes of type List or Map. -- -- A /QueryFilter/ is applied after the items have already been read; the process of filtering does not consume any additional read capacity units. -- -- If you provide more than one condition in the /QueryFilter/ map, then by default all of the conditions must evaluate to true. In other words, the conditions are ANDed together. (You can use the /ConditionalOperator/ parameter to OR the conditions instead. If you do this, then at least one of the conditions must evaluate to true, rather than all of them.) -- -- Note that /QueryFilter/ does not allow key attributes. You cannot define a filter condition on a partition key or a sort key. -- -- Each /QueryFilter/ element consists of an attribute name to compare, along with the following: -- -- - /AttributeValueList/ - One or more values to evaluate against the supplied attribute. The number of values in the list depends on the operator specified in /ComparisonOperator/. -- -- For type Number, value comparisons are numeric. -- -- String value comparisons for greater than, equals, or less than are based on ASCII character code values. For example, 'a' is greater than 'A', and 'a' is greater than 'B'. For a list of code values, see . -- -- For type Binary, DynamoDB treats each byte of the binary data as unsigned when it compares binary values. -- -- For information on specifying data types in JSON, see in the /Amazon DynamoDB Developer Guide/. -- -- - /ComparisonOperator/ - A comparator for evaluating attributes. For example, equals, greater than, less than, etc. -- -- The following comparison operators are available: -- -- 'EQ | NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH | IN | BETWEEN' -- -- For complete descriptions of all comparison operators, see the data type. -- qQueryFilter :: Lens' Query (HashMap Text Condition) qQueryFilter = lens _qQueryFilter (\ s a -> s{_qQueryFilter = a}) . _Default . _Map; -- | Determines the read consistency model: If set to 'true', then the operation uses strongly consistent reads; otherwise, the operation uses eventually consistent reads. -- -- Strongly consistent reads are not supported on global secondary indexes. If you query a global secondary index with /ConsistentRead/ set to 'true', you will receive a /ValidationException/. qConsistentRead :: Lens' Query (Maybe Bool) qConsistentRead = lens _qConsistentRead (\ s a -> s{_qConsistentRead = a}); -- | One or more values that can be substituted in an expression. -- -- Use the __:__ (colon) character in an expression to dereference an attribute value. For example, suppose that you wanted to check whether the value of the /ProductStatus/ attribute was one of the following: -- -- 'Available | Backordered | Discontinued' -- -- You would first need to specify /ExpressionAttributeValues/ as follows: -- -- '{ \":avail\":{\"S\":\"Available\"}, \":back\":{\"S\":\"Backordered\"}, \":disc\":{\"S\":\"Discontinued\"} }' -- -- You could then use these values in an expression, such as this: -- -- 'ProductStatus IN (:avail, :back, :disc)' -- -- For more information on expression attribute values, see in the /Amazon DynamoDB Developer Guide/. qExpressionAttributeValues :: Lens' Query (HashMap Text AttributeValue) qExpressionAttributeValues = lens _qExpressionAttributeValues (\ s a -> s{_qExpressionAttributeValues = a}) . _Default . _Map; -- | Undocumented member. qReturnConsumedCapacity :: Lens' Query (Maybe ReturnConsumedCapacity) qReturnConsumedCapacity = lens _qReturnConsumedCapacity (\ s a -> s{_qReturnConsumedCapacity = a}); -- | Specifies the order for index traversal: If 'true' (default), the traversal is performed in ascending order; if 'false', the traversal is performed in descending order. -- -- Items with the same partition key value are stored in sorted order by sort key. If the sort key data type is Number, the results are stored in numeric order. For type String, the results are stored in order of ASCII character code values. For type Binary, DynamoDB treats each byte of the binary data as unsigned. -- -- If /ScanIndexForward/ is 'true', DynamoDB returns the results in the order in which they are stored (by sort key value). This is the default behavior. If /ScanIndexForward/ is 'false', DynamoDB reads the results in reverse order by sort key value, and then returns the results to the client. qScanIndexForward :: Lens' Query (Maybe Bool) qScanIndexForward = lens _qScanIndexForward (\ s a -> s{_qScanIndexForward = a}); -- | The maximum number of items to evaluate (not necessarily the number of matching items). If DynamoDB processes the number of items up to the limit while processing the results, it stops the operation and returns the matching values up to that point, and a key in /LastEvaluatedKey/ to apply in a subsequent operation, so that you can pick up where you left off. Also, if the processed data set size exceeds 1 MB before DynamoDB reaches this limit, it stops the operation and returns the matching values up to the limit, and a key in /LastEvaluatedKey/ to apply in a subsequent operation to continue the operation. For more information, see in the /Amazon DynamoDB Developer Guide/. qLimit :: Lens' Query (Maybe Natural) qLimit = lens _qLimit (\ s a -> s{_qLimit = a}) . mapping _Nat; -- | The attributes to be returned in the result. You can retrieve all item attributes, specific item attributes, the count of matching items, or in the case of an index, some or all of the attributes projected into the index. -- -- - 'ALL_ATTRIBUTES' - Returns all of the item attributes from the specified table or index. If you query a local secondary index, then for each matching item in the index DynamoDB will fetch the entire item from the parent table. If the index is configured to project all item attributes, then all of the data can be obtained from the local secondary index, and no fetching is required. -- -- - 'ALL_PROJECTED_ATTRIBUTES' - Allowed only when querying an index. Retrieves all attributes that have been projected into the index. If the index is configured to project all attributes, this return value is equivalent to specifying 'ALL_ATTRIBUTES'. -- -- - 'COUNT' - Returns the number of matching items, rather than the matching items themselves. -- -- - 'SPECIFIC_ATTRIBUTES' - Returns only the attributes listed in /AttributesToGet/. This return value is equivalent to specifying /AttributesToGet/ without specifying any value for /Select/. -- -- If you query a local secondary index and request only attributes that are projected into that index, the operation will read only the index and not the table. If any of the requested attributes are not projected into the local secondary index, DynamoDB will fetch each of these attributes from the parent table. This extra fetching incurs additional throughput cost and latency. -- -- If you query a global secondary index, you can only request attributes that are projected into the index. Global secondary index queries cannot fetch attributes from the parent table. -- -- If neither /Select/ nor /AttributesToGet/ are specified, DynamoDB defaults to 'ALL_ATTRIBUTES' when accessing a table, and 'ALL_PROJECTED_ATTRIBUTES' when accessing an index. You cannot use both /Select/ and /AttributesToGet/ together in a single request, unless the value for /Select/ is 'SPECIFIC_ATTRIBUTES'. (This usage is equivalent to specifying /AttributesToGet/ without any value for /Select/.) -- -- If you use the /ProjectionExpression/ parameter, then the value for /Select/ can only be 'SPECIFIC_ATTRIBUTES'. Any other value for /Select/ will return an error. qSelect :: Lens' Query (Maybe Select) qSelect = lens _qSelect (\ s a -> s{_qSelect = a}); -- | The condition that specifies the key value(s) for items to be retrieved by the /Query/ action. -- -- The condition must perform an equality test on a single partition key value. The condition can also perform one of several comparison tests on a single sort key value. /Query/ can use /KeyConditionExpression/ to retrieve one item with a given partition key value and sort key value, or several items that have the same partition key value but different sort key values. -- -- The partition key equality test is required, and must be specified in the following format: -- -- 'partitionKeyName' /=/ ':partitionkeyval' -- -- If you also want to provide a condition for the sort key, it must be combined using /AND/ with the condition for the sort key. Following is an example, using the __=__ comparison operator for the sort key: -- -- 'partitionKeyName' /=/ ':partitionkeyval' /AND/ 'sortKeyName' /=/ ':sortkeyval' -- -- Valid comparisons for the sort key condition are as follows: -- -- - 'sortKeyName' /=/ ':sortkeyval' - true if the sort key value is equal to ':sortkeyval'. -- -- - 'sortKeyName' /</ ':sortkeyval' - true if the sort key value is less than ':sortkeyval'. -- -- - 'sortKeyName' /<=/ ':sortkeyval' - true if the sort key value is less than or equal to ':sortkeyval'. -- -- - 'sortKeyName' />/ ':sortkeyval' - true if the sort key value is greater than ':sortkeyval'. -- -- - 'sortKeyName' />=/ ':sortkeyval' - true if the sort key value is greater than or equal to ':sortkeyval'. -- -- - 'sortKeyName' /BETWEEN/ ':sortkeyval1' /AND/ ':sortkeyval2' - true if the sort key value is greater than or equal to ':sortkeyval1', and less than or equal to ':sortkeyval2'. -- -- - /begins_with (/'sortKeyName', ':sortkeyval'/)/ - true if the sort key value begins with a particular operand. (You cannot use this function with a sort key that is of type Number.) Note that the function name 'begins_with' is case-sensitive. -- -- Use the /ExpressionAttributeValues/ parameter to replace tokens such as ':partitionval' and ':sortval' with actual values at runtime. -- -- You can optionally use the /ExpressionAttributeNames/ parameter to replace the names of the partition key and sort key with placeholder tokens. This option might be necessary if an attribute name conflicts with a DynamoDB reserved word. For example, the following /KeyConditionExpression/ parameter causes an error because /Size/ is a reserved word: -- -- - 'Size = :myval' -- -- To work around this, define a placeholder (such a '#S') to represent the attribute name /Size/. /KeyConditionExpression/ then is as follows: -- -- - '#S = :myval' -- -- For a list of reserved words, see in the /Amazon DynamoDB Developer Guide/. -- -- For more information on /ExpressionAttributeNames/ and /ExpressionAttributeValues/, see in the /Amazon DynamoDB Developer Guide/. -- -- /KeyConditionExpression/ replaces the legacy /KeyConditions/ parameter. qKeyConditionExpression :: Lens' Query (Maybe Text) qKeyConditionExpression = lens _qKeyConditionExpression (\ s a -> s{_qKeyConditionExpression = a}); -- | This is a legacy parameter, for backward compatibility. New applications should use /FilterExpression/ instead. Do not combine legacy parameters and expression parameters in a single API call; otherwise, DynamoDB will return a /ValidationException/ exception. -- -- A logical operator to apply to the conditions in a /QueryFilter/ map: -- -- - 'AND' - If all of the conditions evaluate to true, then the entire map evaluates to true. -- -- - 'OR' - If at least one of the conditions evaluate to true, then the entire map evaluates to true. -- -- If you omit /ConditionalOperator/, then 'AND' is the default. -- -- The operation will succeed only if the entire map evaluates to true. -- -- This parameter does not support attributes of type List or Map. qConditionalOperator :: Lens' Query (Maybe ConditionalOperator) qConditionalOperator = lens _qConditionalOperator (\ s a -> s{_qConditionalOperator = a}); -- | The primary key of the first item that this operation will evaluate. Use the value that was returned for /LastEvaluatedKey/ in the previous operation. -- -- The data type for /ExclusiveStartKey/ must be String, Number or Binary. No set data types are allowed. qExclusiveStartKey :: Lens' Query (HashMap Text AttributeValue) qExclusiveStartKey = lens _qExclusiveStartKey (\ s a -> s{_qExclusiveStartKey = a}) . _Default . _Map; -- | The name of an index to query. This index can be any local secondary index or global secondary index on the table. Note that if you use the /IndexName/ parameter, you must also provide /TableName./ qIndexName :: Lens' Query (Maybe Text) qIndexName = lens _qIndexName (\ s a -> s{_qIndexName = a}); -- | The name of the table containing the requested items. qTableName :: Lens' Query Text qTableName = lens _qTableName (\ s a -> s{_qTableName = a}); instance AWSPager Query where page rq rs | stop (rs ^. qrsLastEvaluatedKey) = Nothing | stop (rs ^. qrsItems) = Nothing | stop (rs ^. qrsCount) = Nothing | stop (rs ^. qrsScannedCount) = Nothing | otherwise = Just $ rq & qExclusiveStartKey .~ rs ^. qrsLastEvaluatedKey instance AWSRequest Query where type Rs Query = QueryResponse request = postJSON dynamoDB response = receiveJSON (\ s h x -> QueryResponse' <$> (x .?> "LastEvaluatedKey" .!@ mempty) <*> (x .?> "Count") <*> (x .?> "ScannedCount") <*> (x .?> "Items" .!@ mempty) <*> (x .?> "ConsumedCapacity") <*> (pure (fromEnum s))) instance Hashable Query instance NFData Query instance ToHeaders Query where toHeaders = const (mconcat ["X-Amz-Target" =# ("DynamoDB_20120810.Query" :: ByteString), "Content-Type" =# ("application/x-amz-json-1.0" :: ByteString)]) instance ToJSON Query where toJSON Query'{..} = object (catMaybes [("KeyConditions" .=) <$> _qKeyConditions, ("ProjectionExpression" .=) <$> _qProjectionExpression, ("AttributesToGet" .=) <$> _qAttributesToGet, ("ExpressionAttributeNames" .=) <$> _qExpressionAttributeNames, ("FilterExpression" .=) <$> _qFilterExpression, ("QueryFilter" .=) <$> _qQueryFilter, ("ConsistentRead" .=) <$> _qConsistentRead, ("ExpressionAttributeValues" .=) <$> _qExpressionAttributeValues, ("ReturnConsumedCapacity" .=) <$> _qReturnConsumedCapacity, ("ScanIndexForward" .=) <$> _qScanIndexForward, ("Limit" .=) <$> _qLimit, ("Select" .=) <$> _qSelect, ("KeyConditionExpression" .=) <$> _qKeyConditionExpression, ("ConditionalOperator" .=) <$> _qConditionalOperator, ("ExclusiveStartKey" .=) <$> _qExclusiveStartKey, ("IndexName" .=) <$> _qIndexName, Just ("TableName" .= _qTableName)]) instance ToPath Query where toPath = const "/" instance ToQuery Query where toQuery = const mempty -- | Represents the output of a /Query/ operation. -- -- /See:/ 'queryResponse' smart constructor. data QueryResponse = QueryResponse' { _qrsLastEvaluatedKey :: !(Maybe (Map Text AttributeValue)) , _qrsCount :: !(Maybe Int) , _qrsScannedCount :: !(Maybe Int) , _qrsItems :: !(Maybe [Map Text AttributeValue]) , _qrsConsumedCapacity :: !(Maybe ConsumedCapacity) , _qrsResponseStatus :: !Int } deriving (Eq,Read,Show,Data,Typeable,Generic) -- | Creates a value of 'QueryResponse' with the minimum fields required to make a request. -- -- Use one of the following lenses to modify other fields as desired: -- -- * 'qrsLastEvaluatedKey' -- -- * 'qrsCount' -- -- * 'qrsScannedCount' -- -- * 'qrsItems' -- -- * 'qrsConsumedCapacity' -- -- * 'qrsResponseStatus' queryResponse :: Int -- ^ 'qrsResponseStatus' -> QueryResponse queryResponse pResponseStatus_ = QueryResponse' { _qrsLastEvaluatedKey = Nothing , _qrsCount = Nothing , _qrsScannedCount = Nothing , _qrsItems = Nothing , _qrsConsumedCapacity = Nothing , _qrsResponseStatus = pResponseStatus_ } -- | The primary key of the item where the operation stopped, inclusive of the previous result set. Use this value to start a new operation, excluding this value in the new request. -- -- If /LastEvaluatedKey/ is empty, then the \"last page\" of results has been processed and there is no more data to be retrieved. -- -- If /LastEvaluatedKey/ is not empty, it does not necessarily mean that there is more data in the result set. The only way to know when you have reached the end of the result set is when /LastEvaluatedKey/ is empty. qrsLastEvaluatedKey :: Lens' QueryResponse (HashMap Text AttributeValue) qrsLastEvaluatedKey = lens _qrsLastEvaluatedKey (\ s a -> s{_qrsLastEvaluatedKey = a}) . _Default . _Map; -- | The number of items in the response. -- -- If you used a /QueryFilter/ in the request, then /Count/ is the number of items returned after the filter was applied, and /ScannedCount/ is the number of matching items before the filter was applied. -- -- If you did not use a filter in the request, then /Count/ and /ScannedCount/ are the same. qrsCount :: Lens' QueryResponse (Maybe Int) qrsCount = lens _qrsCount (\ s a -> s{_qrsCount = a}); -- | The number of items evaluated, before any /QueryFilter/ is applied. A high /ScannedCount/ value with few, or no, /Count/ results indicates an inefficient /Query/ operation. For more information, see in the /Amazon DynamoDB Developer Guide/. -- -- If you did not use a filter in the request, then /ScannedCount/ is the same as /Count/. qrsScannedCount :: Lens' QueryResponse (Maybe Int) qrsScannedCount = lens _qrsScannedCount (\ s a -> s{_qrsScannedCount = a}); -- | An array of item attributes that match the query criteria. Each element in this array consists of an attribute name and the value for that attribute. qrsItems :: Lens' QueryResponse [HashMap Text AttributeValue] qrsItems = lens _qrsItems (\ s a -> s{_qrsItems = a}) . _Default . _Coerce; -- | Undocumented member. qrsConsumedCapacity :: Lens' QueryResponse (Maybe ConsumedCapacity) qrsConsumedCapacity = lens _qrsConsumedCapacity (\ s a -> s{_qrsConsumedCapacity = a}); -- | The response status code. qrsResponseStatus :: Lens' QueryResponse Int qrsResponseStatus = lens _qrsResponseStatus (\ s a -> s{_qrsResponseStatus = a}); instance NFData QueryResponse