Yandex.Cloud
  • Services
  • Why Yandex.Cloud
  • Pricing
  • Documentation
  • Contact us
Get started
Yandex Database
  • Getting started
    • Overview
    • Create databases
    • Examples of YQL queries
    • Examples of operations in the YDB CLI
    • Launch a test app
    • Document API
    • Developing in NodeJS through the Document API
  • Step-by-step instructions
    • Database management
    • How to connect to a database
    • Table management
    • Reading and writing data
    • Working with secondary indexes
  • Working with the SDK
  • Concepts
    • Overview
    • Data model and schema
    • Serverless and Dedicated operation modes
    • Data types
    • Transactions
    • Secondary indexes
    • Time to Live (TTL)
    • Terms and definitions
    • Quotas and limits
  • Access management
  • Pricing policy
    • Overview
    • Serverless mode
    • Dedicated mode
  • Recommendations
    • Schema design
    • Partitioning tables
    • Secondary indexes
    • Paginated output
    • Loading large data volumes
    • Using timeouts
  • YDB API and API reference
    • Database limits
    • Handling errors in the API
  • Amazon DynamoDB-compatible HTTP API
    • API reference
      • All methods
      • Actions
        • BatchGetItem
        • BatchWriteItem
        • CreateTable
        • DeleteItem
        • DeleteTable
        • DescribeTable
        • GetItem
        • ListTables
        • PutItem
        • Query
        • Scan
        • TransactGetItems
        • TransactWriteItems
        • UpdateItem
      • Common errors
  • YQL reference guide
    • Overview
    • Data types
      • Simple
      • Optional
      • Containers
      • Special
    • Syntax
      • Unsupported statements
      • For text representation of data types
      • Expressions
      • CREATE TABLE
      • DROP TABLE
      • INSERT INTO
      • UPSERT INTO
      • REPLACE INTO
      • UPDATE
      • DELETE
      • SELECT
      • GROUP BY
      • JOIN
      • FLATTEN
      • ACTION
      • DISCARD
      • PRAGMA
      • DECLARE
      • OVER, PARTITION BY, and WINDOW
    • Built-in functions
      • Basic
      • Aggregate
      • Window
      • For lists
      • For dictionaries
      • For JSON
      • For structures
      • For types
    • Preset user-defined functions
      • HyperScan
      • Pcre
      • Pire
      • Re2
      • String
      • Unicode
      • Datetime
      • Url
      • Ip
      • Digest
      • Math
      • Histogram
    • For text representation of data types
  • YQL tutorial
    • Overview
    • Creating a table
    • Adding data to a table
    • Selecting data from all columns
    • Selecting data from specific columns
    • Sorting and filtering
    • Data aggregation
    • Additional selection criteria
    • Joining tables by JOIN
    • Data insert and update by REPLACE
    • Data insert and update by UPSERT
    • Data insert by INSERT
    • Data update by UPDATE
    • Deleting data
    • Adding and deleting columns
    • Deleting a table
  • Maintenance
    • Backups
  • Diagnostics
    • System views
  • Questions and answers
    • General questions
    • Errors
    • YQL
    • All questions on the same page
  • Public materials
  1. YQL reference guide
  2. Syntax
  3. DISCARD

DISCARD

    Calculates SELECT, PROCESS, or REDUCE, but doesn't return the result to either the client or table.

    It's good to combine it with Ensure to check the final calculation result against the user's criteria.

    Examples

    DISCARD SELECT 1;
    
    INSERT INTO result_table WITH TRUNCATE
    SELECT * FROM
    my_table
    WHERE value % 2 == 0;
    
    COMMIT:
    
    DISCARD SELECT Ensure(
        0, -- will discard result anyway
        COUNT(*) > 1000,
        "Too small result table, got only " || CAST(COUNT(*) AS String) || " rows"
    ) FROM result_table;
    
    Language
    Careers
    Privacy policy
    Terms of use
    © 2021 Yandex.Cloud LLC