Working with Impala
IMPORTANT This component is deprecated. Hewlett Packard
Enterprise recommends using an alternate product. For more information, see Discontinued Ecosystem Components.
After you start Impala, use the impala-shell or a JDBC or ODBC client to query data. You can query data stored in files, as well as data stored in MapR Database tables. Impala depends on the Hive metastore to track table metadata. The MapR filesystem tracks the metadata of other files. Impala supports Text and Parquet file formats. If you want to query data using SequenceFile, RCFile, and Avro file formats, use Hive to load the data. Impala supports Snappy, GZIP, Deflate, and BZIP compression codecs.
Impala File Formats
The following table summarizes the supported Impala text formats:
File Type | Format | Compression Codecs | Can Impala Create? | Can Impala INSERT? |
---|---|---|---|---|
Text | Unstructured | Snappy, GZIP, BZIP | Yes, for CREATE TABLE with no STORED AS clause;default file format is uncompressed text with values separated by ASCII 0x01 characters, typically represented a Ctrl-A | Yes. CREATE TABLE, INSERT, and query. |
SequenceFile | Structured | Snappy, GZIP, deflate, BZIP2 | Yes | No. Query only. Load data using Hive. |
RCFile | Structured | Snappy, GZIP, deflate, BZIP2 | Yes | No. Query only. Load data using Hive. |
Parquet | Structured | Snappy (default), GZIP | Yes | Yes. CREATE TABLE, INSERT, and query. |
Avro | Structured | Snappy, GZIP, deflate, BZIP2 | No, create using Hive. | No. Query only. Load data using Hive. |