Advanced options - Amazon Athena
Fetch sizeEnable result reuseResult reuse maximum ageEnable streaming APIEnable S3 fetcher Use multiple S3 threadsUse single catalog and schemaUse query to list tablesUse WCHAR for string typesQuery external catalogsVerify SSLS3 result block sizeString column lengthComplex type column lengthTrusted CA certificateMin poll periodMax poll periodPoll multiplierMax poll durationConnection timeoutRequest timeout
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Advanced options

Fetch size

The maximum number of results (rows) to return in this request. For parameter information, see GetQuery MaxResults. For the streaming API, the maximum value is 10000000.

Connection string name Parameter type Default value Connection string example
RowsToFetchPerBlock Optional

1000 for non-streaming

20000 for streaming

 RowsToFetchPerBlock=20000;

Enable result reuse

Specifies if previous query results can be reused when the query is run. For parameter information, see ResultReuseByAgeConfiguration.

Connection string name Parameter type Default value Connection string example
EnableResultReuse Optional 0 EnableResultReuse=1;

Result reuse maximum age

Specifies, in minutes, the maximum age of a previous query result that Athena should consider for reuse. For parameter information, see ResultReuseByAgeConfiguration.

Connection string name Parameter type Default value Connection string example
ReusedResultMaxAgeInMinutes Optional 60 ReusedResultMaxAgeInMinutes=90;

Enable streaming API

Chooses whether to use the Athena streaming API to fetch the result set.

Connection string name Parameter type Default value Connection string example
UseResultsetStreaming Optional 0 UseResultsetStreaming=1;

Enable S3 fetcher

Fetches the result set generated by Athena from the Amazon S3 bucket by interacting with Amazon S3 directly.

Connection string name Parameter type Default value Connection string example
EnableS3Fetcher Optional 1 EnableS3Fetcher=1;

Use multiple S3 threads

Fetches data from Amazon S3 using multiple threads. When this option is enabled, the result file stored in the Amazon S3 bucket is fetched in parallel using multiple threads.

Enable this option only if you have good network bandwidth. For example, in our measurements on an EC2 c5.2xlarge instance, a single-threaded S3 client reached 1 Gbps, while multiple-threaded S3 clients reached 4 Gbps of network throughput.

Connection string name Parameter type Default value Connection string example

UseMultipleS3Threads

 Optional 0 UseMultipleS3Threads=1;

Use single catalog and schema

By default, the ODBC driver queries Athena to get the list of available catalogs and schemas. This option forces the driver to use the catalog and schema specified by the ODBC Data Source Administrator configuration dialog box or connection parameters.

Connection string name Parameter type Default value Connection string example
UseSingleCatalogAndSchema Optional 0 UseSingleCatalogAndSchema=1;

Use query to list tables

For LAMBDA catalog types, enables the ODBC driver to submit a SHOW TABLES query to get a list of available tables. This setting is the default. If this parameter is set to 0, the ODBC driver uses the Athena ListTableMetadata API to get a list of available tables. Note that, for LAMBDA catalog types, using ListTableMetadata leads to performance regression.

Connection string name Parameter type Default value Connection string example
UseQueryToListTables Optional 1 UseQueryToListTables=1;

Use WCHAR for string types

By default, the ODBC driver uses SQL_CHAR and SQL_VARCHAR for Athena the string data types char, varchar, string, array, map<>, struct<>, and row. Setting this parameter to 1 forces the driver to use SQL_WCHAR and SQL_WVARCHAR for string data types. Wide character and wide variable character types are used to ensure that characters from different languages can be stored and retrieved correctly.

Connection string name Parameter type Default value Connection string example
UseWCharForStringTypes Optional 0 UseWCharForStringTypes=1;

Query external catalogs

Specifies if the driver needs to query external catalogs from Athena. For more information, see Migrate to the ODBC 2.x driver.

Connection string name Parameter type Default value Connection string example
QueryExternalCatalogs Optional 0 QueryExternalCatalogs=1;

Verify SSL

Controls whether to verify SSL certificates when you use the Amazon SDK. This value is passed to ClientConfiguration.verifySSL parameter. For more information, see Amazon Client configuration in the Amazon SDK for C++ Developer Guide.

Connection string name Parameter type Default value Connection string example
VerifySSL Optional 1 VerifySSL=0;

S3 result block size

Specifies, in bytes, the size of the block to download for a single Amazon S3 GetObject API request. The default value is 67108864 (64 MB). The minimum and maximum values allowed are 10485760 (10 MB) and 2146435072 (about 2 GB).

Connection string name Parameter type Default value Connection string example
S3ResultBlockSize Optional 67108864 S3ResultBlockSize=268435456;

String column length

Specifies the column length for columns with the string data type. Because Athena uses the Apache Hive string data type, which does not have defined precision, the default length reported by Athena is 2147483647 (INT_MAX). Because BI tools usually pre-allocate memory for columns, this can lead to high memory consumption. To avoid this, the Athena ODBC driver limits the reported precision for columns of the string data type and exposes the StringColumnLength connection parameter so that the default value can be changed.

Connection string name Parameter type Default value Connection string example
StringColumnLength Optional 255 StringColumnLength=65535;

Complex type column length

Specifies the column length for columns with complex data types like map, struct, and array. Like StringColumnLength, Athena reports 0 precision for columns with complex data types. The Athena ODBC driver sets the default precision for columns with complex data types and exposes the ComplexTypeColumnLength connection parameter so that the default value can be changed.

Connection string name Parameter type Default value Connection string example
ComplexTypeColumnLength Optional 65535 ComplexTypeColumnLength=123456;

Trusted CA certificate

Instructs the HTTP client where to find your SSL certificate trust store. This value is passed to the ClientConfiguration.caFile parameter. For more information, see Amazon Client configuration in the Amazon SDK for C++ Developer Guide.

Connection string name Parameter type Default value Connection string example
TrustedCerts Optional %INSTALL_PATH%/bin TrustedCerts=C:\\Program Files\\Amazon Athena ODBC Driver\\bin\\cacert.pem;

Min poll period

Specifies the minimum value in milliseconds to wait before polling Athena for query execution status.

Connection string name Parameter type Default value Connection string example
MinQueryExecutionPollingInterval Optional 100 MinQueryExecutionPollingInterval=200;

Max poll period

Specifies the maximum value in milliseconds to wait before polling Athena for the query execution status.

Connection string name Parameter type Default value Connection string example
MaxQueryExecutionPollingInterval Optional 60000 MaxQueryExecutionPollingInterval=1000;

Poll multiplier

Specifies the factor for increasing the poll period. By default, polling begins with the value of min poll period and doubles with each poll until it reaches the value of max poll period.

Connection string name Parameter type Default value Connection string example
QueryExecutionPollingIntervalMultiplier Optional 2 QueryExecutionPollingIntervalMultiplier=2;

Max poll duration

Specifies the maximum value in milliseconds that a driver can poll Athena for query execution status.

Connection string name Parameter type Default value Connection string example
MaxPollDuration Optional 1800000 MaxPollDuration=1800000;

Connection timeout

The amount of time (in milliseconds) that the HTTP connection waits to establish a connection. This value is set for ClientConfiguration.connectTimeoutMs Athena client. If not specified, the curl default value is used. For information about connection parameters, see Client Configuration in the Amazon SDK for Java Developer Guide.

Connection string name Parameter type Default value Connection string example
ConnectionTimeout Optional 0 ConnectionTimeout=2000;

Request timeout

Specifies the socket read timeout for HTTP clients. This value is set for the ClientConfiguration.requestTimeoutMs parameter of the Athena client. For parameter information, see Client Configuration in the Amazon SDK for Java Developer Guide.

Connection string name Parameter type Default value Connection string example
RequestTimeout Optional 10000 RequestTimeout=30000;