Cloudera Impala
| Type of Support: | Read & Write; In-Database |
| Validated On: | Impala 2.6.0; Simba Impala Driver 1.2.11.1016 |
| Connection Type: | ODBC (32- and 64-bit) |
| Driver Details: |
The ODBC driver can be downloaded here. Certified with CDH 5.8. In-Database processing requires 64-bit database drivers.
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Alteryx tools used to connect
- Input Data Tool and Output Data Tool (Standard workflow processing)
- Connect In-DB Tool and Data Stream In Tool (In-database workflow processing)
Additional Details
If you are using Windows Kerberos authentication (via SSPI), you must select the "Use Only SSPI - Enable for this DSN" option within the Simba Impala ODBC driver Advanced Options.
If you have issues with reading or writing Unicode® characters, access the Simba Impala ODBC driver. Under Advanced Options, select the “Use SQL Unicode Types” option.
Write Support
The Impala ODBC driver supports both the Impala write capability and HDFS connection options via one of the following two methods:
- For a standard workflow use the Output Data Tool. Select the Hadoop connection option, and then select HDFS Avro or HDFS CSV for the File Format.
- For an In-Database workflow use the Connect In-DB Tool or the Data Stream In Tool. Establish a Read connection. On the Write tab select HDFS Avro or HDFS (CSV) for the Driver.
Limitations
Field Names
- To write a table with field names that total more than 4000 characters, use CSV instead of Avro.
- When creating field names and writing queries in Impala, note that identifiers (names of databases, tables or columns) in Impala have certain restrictions. While reserved keywords are supported, other identifiers are not supported. For example:
- Identifiers cannot have a space.
- Identifiers cannot begin with a number (e.g., 1st is invalid)
- Identifiers can only be alphanumeric (e.g., no percent sign (tax%), dollar sign (money$), symbols (>, < etc) or any other non-ASCII characters.
- Identifiers are case insensitive (e.g., T1 and t1 are the same identifier)
Character Support
- Quoted fields in table styles are not supported.
- Unicode® characters are not supported.
SQL Support
Delete and Append statements are not supported.
Strings and Integer Support
- Strings are limited to 32,767 bytes.
- The TINYINT data type range is -128 to 127 and therefore needs to be mapped to INT16.
In-Database
- Due to an Impala database limitation, you cannot select a table with the Connect In-DB Tool and then write to HDFS Avro with either the Overwrite Table (Drop) or Create New Table Creation Mode in the Write Data In-DB Tool.