hdfs_* session settings

These settings are available in system.settings and are autogenerated from source.

hdfs_create_new_file_on_insert

Enables or disables creating a new file on each insert in HDFS engine tables. If enabled, on each insert a new HDFS file will be created with the name, similar to this pattern:

initial: data.Parquet.gz -> data.1.Parquet.gz -> data.2.Parquet.gz, etc.

Possible values:

• 0 — INSERT query appends new data to the end of the file.
• 1 — INSERT query creates a new file.

hdfs_ignore_file_doesnt_exist

Ignore absence of file if it does not exist when reading certain keys.

Possible values:

• 1 — SELECT returns empty result.
• 0 — SELECT throws an exception.

hdfs_replication

The actual number of replications can be specified when the hdfs file is created.

hdfs_skip_empty_files

Enables or disables skipping empty files in HDFS engine tables.

Possible values:

• 0 — SELECT throws an exception if empty file is not compatible with requested format.
• 1 — SELECT returns empty result for empty file.

hdfs_throw_on_zero_files_match

Throw an error if matched zero files according to glob expansion rules.

Possible values:

• 1 — SELECT throws an exception.
• 0 — SELECT returns empty result.

hdfs_truncate_on_insert

Enables or disables truncation before an insert in hdfs engine tables. If disabled, an exception will be thrown on an attempt to insert if a file in HDFS already exists.

Possible values:

• 0 — INSERT query appends new data to the end of the file.
• 1 — INSERT query replaces existing content of the file with the new data.