DESCRIBE MATERIALIZED VIEW

Shows the definition of one materialized view as an executable CQL statement.

Synopsis

DESCRIBE MATERIALIZED VIEW [<keyspace_name>.]<view_name>

Legend
Syntax conventions	Description
UPPERCASE	Literal keyword.
Lowercase	Not literal.
`< >`	Variable value. Replace with a user-defined value.
`[]`	Optional. Square brackets (`[]`) surround optional command arguments. Do not type the square brackets.
`( )`	Group. Parentheses ( `( )` ) identify a group to choose from. Do not type the parentheses.
`\|`	Or. A vertical bar (`\|`) separates alternative elements. Type any one of the elements. Do not type the vertical bar.
`...`	Repeatable. An ellipsis ( `...` ) indicates that you can repeat the syntax element as often as required.
`'<Literal string>'`	Single quotation (`'`) marks must surround literal strings in CQL statements. Use single quotation marks to preserve upper case.
`{ <key> : <value> }`	Map collection. Braces (`{ }`) enclose map collections or key value pairs. A colon separates the key and the value.
`<<datatype1>,<datatype2>>`	Set, list, map, or tuple. Angle brackets ( `< >` ) enclose data types in a set, list, map, or tuple. Separate the data types with a comma.
`<cql_statement>;`	End CQL statement. A semicolon (`;`) terminates all CQL statements.
`[--]`	Separate the command line options from the command arguments with two hyphens ( `--` ). This syntax is useful when arguments might be mistaken for command line options.
`' <<schema\> ... </schema\>> '`	Search CQL only: Single quotation marks (`'`) surround an entire XML schema declaration.
`@<xml_entity>='<xml_entity_type>'`	Search CQL only: Identify the entity and literal value to overwrite the XML element in the schema and solrConfig files.

DESCRIBE MATERIALIZED VIEW: Get one materialized view specified by name.

The short form is DESC MATERIALIZED VIEW.
<keyspace_name>: Optional. Name of the keyspace containing the materialized view. If not specified, the current keyspace is used.
<view_name>: Name of the materialized view to describe.

On Linux systems, object names, such as keyspace and table names, are case-sensitive. CQL converts object names to lowercase unless enclosed in double quotation marks.

Examples

Get the definition of the cyclist_by_birthday materialized view in the cycling keyspace:

DESC MATERIALIZED VIEW cycling.cyclist_by_birthday;

If the materialized view exists, the result is the materialized view definition as an executable CQL statement. For example:

CREATE MATERIALIZED VIEW cycling.cyclist_by_birthday AS
  SELECT birthday, cid, age, country, name
  FROM cycling.cyclist_base
  WHERE birthday IS NOT NULL AND cid IS NOT NULL
  PRIMARY KEY (birthday, cid)
  WITH CLUSTERING ORDER BY (cid ASC)
    AND bloom_filter_fp_chance = 0.01
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}
    AND comment = ''
    AND compaction = {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy',
      'max_threshold': '32', 'min_threshold': '4'}
    AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'}
    AND crc_check_chance = 1.0
    AND default_time_to_live = 0
    AND gc_grace_seconds = 864000
    AND max_index_interval = 2048
    AND memtable_flush_period_in_ms = 0
    AND min_index_interval = 128
    AND speculative_retry = '99PERCENTILE';

You can use the output to re-create a materialized view in another environment if a valid base table exists. The base table name is specified in the FROM clause of the materialized view definition. To get the base table definition, use DESCRIBE TABLE.

The contents of the WITH clause depends on your materialized view and cluster configuration. Unspecified options fallback to default values if not explicitly set in CREATE MATERIALIZED VIEW.

DESCRIBE MATERIALIZED VIEW

Synopsis

Examples

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