@aws-sdk/client-dynamodb
Version:
AWS SDK for JavaScript Dynamodb Client for Node.js, Browser and React Native
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JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.ScanCommand = void 0;
const models_0_1 = require("../models/models_0");
const Aws_json1_0_1 = require("../protocols/Aws_json1_0");
const middleware_serde_1 = require("@aws-sdk/middleware-serde");
const smithy_client_1 = require("@aws-sdk/smithy-client");
/**
* <p>The <code>Scan</code> operation returns one or more items and item attributes by accessing every
* item in a table or a secondary index. To have DynamoDB return fewer items, you can provide a <code>FilterExpression</code> operation.</p>
* <p>If the total number of scanned items exceeds the maximum dataset size limit of 1 MB, the
* scan stops and results are returned to the user as a <code>LastEvaluatedKey</code> value
* to continue the scan in a subsequent operation. The results also include the number of
* items exceeding the limit. A scan can result in no table data meeting the filter
* criteria. </p>
* <p>A single <code>Scan</code> operation reads up to the maximum number of items set (if
* using the <code>Limit</code> parameter) or a maximum of 1 MB of data and then apply any
* filtering to the results using <code>FilterExpression</code>. If
* <code>LastEvaluatedKey</code> is present in the response, you need to paginate the
* result set. For more information, see <a href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Scan.html#Scan.Pagination">Paginating the
* Results</a> in the <i>Amazon DynamoDB Developer Guide</i>. </p>
* <p>
* <code>Scan</code> operations proceed sequentially; however, for faster performance on
* a large table or secondary index, applications can request a parallel <code>Scan</code>
* operation by providing the <code>Segment</code> and <code>TotalSegments</code>
* parameters. For more information, see <a href="https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Scan.html#Scan.ParallelScan">Parallel
* Scan</a> in the <i>Amazon DynamoDB Developer Guide</i>.</p>
* <p>
* <code>Scan</code> uses eventually consistent reads when accessing the data in a
* table; therefore, the result set might not include the changes to data in the table
* immediately before the operation began. If you need a consistent copy of the data, as of
* the time that the <code>Scan</code> begins, you can set the <code>ConsistentRead</code>
* parameter to <code>true</code>.</p>
*/
class ScanCommand extends smithy_client_1.Command {
// Start section: command_properties
// End section: command_properties
constructor(input) {
// Start section: command_constructor
super();
this.input = input;
this.resolved = false;
// End section: command_constructor
}
/**
* @internal
*/
resolveMiddleware(clientStack, configuration, options) {
if (!this.resolved) {
this.middlewareStack.use(middleware_serde_1.getSerdePlugin(configuration, this.serialize, this.deserialize));
this.resolved = true;
}
const stack = clientStack.concat(this.middlewareStack);
const { logger } = configuration;
const clientName = "DynamoDBClient";
const commandName = "ScanCommand";
const handlerExecutionContext = {
logger,
clientName,
commandName,
inputFilterSensitiveLog: models_0_1.ScanInput.filterSensitiveLog,
outputFilterSensitiveLog: models_0_1.ScanOutput.filterSensitiveLog,
};
const { requestHandler } = configuration;
return stack.resolve((request) => requestHandler.handle(request.request, options || {}), handlerExecutionContext);
}
serialize(input, context) {
return Aws_json1_0_1.serializeAws_json1_0ScanCommand(input, context);
}
deserialize(output, context) {
return Aws_json1_0_1.deserializeAws_json1_0ScanCommand(output, context);
}
}
exports.ScanCommand = ScanCommand;
//# sourceMappingURL=ScanCommand.js.map