Create a table

After the keyspace exists, you can create a table by executing mutations. For this example, two tables are created:

  • graphQL command

  • Result

# create two tables (book, reader) in library with a single mutation
# DATA TYPES: TEXT, UUID, SET(TEXT), TUPLE(TEXT, INT, DATE), LIST(UDT)
mutation createTables {
  book: createTable(
    keyspaceName:"library",
    tableName:"book",
    partitionKeys: [ # The keys required to access your data
      { name: "title", type: {basic: TEXT} }
    ]
    clusteringKeys: [
      { name: "author", type: {basic: TEXT} }
    ]
  )
  reader: createTable(
    keyspaceName:"library",
    tableName:"reader",
    partitionKeys: [
      { name: "name", type: {basic: TEXT} }
    ]
    clusteringKeys: [ # Secondary key used to access values within the partition
      { name: "user_id", type: {basic: UUID}, order: "ASC" }
  	]
    values: [
      { name: "birthdate", type: {basic: DATE} }
      { name: "email", type: {basic: SET, info:{ subTypes: [ { basic: TEXT } ] } } }
      { name: "reviews", type: {basic: TUPLE, info: { subTypes: [ { basic: TEXT }, { basic: INT }, { basic: DATE } ] } } }
      { name: "addresses", type: { basic: LIST, info: { subTypes: [ { basic: UDT, info: { name: "address_type", frozen: true } } ] } } }
    ]
  )
}
shell
  "data": {
    "book": true,
    "reader": true
  }
}
plaintext

It is worth noting that one mutation is used to create two tables. Information about partition keys and clustering keys can be found in the CQL reference.

The second table, reader, also defines a column using a user-defined type (UDT).

IF NOT EXISTS option

A table can be created with an option ifNotExists that will only create the table if it does not already exist:

  • graphQL command

  • Result

# create two tables, magazine and article, IF THEY DON'T EXIST
# DATA TYPES: TEXT, INT, LIST(TEXT)

mutation createTableIfNotExists {
  magazine: createTable(
    keyspaceName:"library",
    tableName:"magazine",
    partitionKeys: [ # The keys required to access your data
      { name: "title", type: {basic: TEXT} }
    ]
    clusteringKeys: [ # Secondary key used to access values within the partition
      { name: "pub_yr", type: {basic: INT}, order: "ASC" }
      { name: "pub_mon", type: {basic: INT} }
      { name: "mag_id", type: {basic: INT} }
    ],
    ifNotExists: true,
    values: [ # The values associated with the keys
      { name: "editor", type: {basic: TEXT} }
    ]
  )
  article: createTable(
    keyspaceName:"library",
    tableName:"article",
    partitionKeys: [ # The keys required to access your data
      { name: "title", type: {basic: TEXT} }
    ]
    clusteringKeys: [ # Secondary key used to access values within the partition
      { name: "mtitle", type: {basic: TEXT} }
    ],
    ifNotExists: true,
    values: [ # The values associated with the keys
      { name: "authors", type: {basic:LIST, info:{ subTypes: [ { basic: TEXT } ] } } }
    ]
  )
}
shell
{
  "data": {
    "magazine": true,
    "article": true
  }
}
plaintext

One of these tables includes creating a column with the data type LIST, an ordered collection of text values.