Class: Google::Cloud::Spanner::BatchUpdate

Inherits:
Object
  • Object
show all
Defined in:
lib/google/cloud/spanner/batch_update.rb

Overview

BatchUpdate

Accepts DML statements and optional parameters and types of the parameters for a batch update.

See Transaction#batch_update.

Instance Method Summary collapse

Instance Method Details

#batch_update(sql, params: nil, types: nil) ⇒ Object

Adds a DML statement to a batch update. See Transaction#batch_update.

Examples:

require "google/cloud/spanner"

spanner = Google::Cloud::Spanner.new
db = spanner.client "my-instance", "my-database"

db.transaction do |tx|
  begin
    row_counts = tx.batch_update do |b|
      statement_count = b.batch_update(
        "UPDATE users SET name = 'Charlie' WHERE id = 1"
      )
    end
    puts row_counts.inspect
  rescue Google::Cloud::Spanner::BatchUpdateError => err
    puts err.cause.message
    puts err.row_counts.inspect
  end
end

Update using SQL parameters:

require "google/cloud/spanner"

spanner = Google::Cloud::Spanner.new
db = spanner.client "my-instance", "my-database"

db.transaction do |tx|
  begin
    row_counts = tx.batch_update do |b|
      statement_count = b.batch_update(
        "UPDATE users SET name = 'Charlie' WHERE id = 1",
        params: { id: 1, name: "Charlie" }
      )
    end
    puts row_counts.inspect
  rescue Google::Cloud::Spanner::BatchUpdateError => err
    puts err.cause.message
    puts err.row_counts.inspect
  end
end

Parameters:

  • sql (String)

    The DML statement string. See Query syntax.

    The DML statement string can contain parameter placeholders. A parameter placeholder consists of "@" followed by the parameter name. Parameter names consist of any combination of letters, numbers, and underscores.

  • params (Hash) (defaults to: nil)

    Parameters for the DML statement string. The parameter placeholders, minus the "@", are the the hash keys, and the literal values are the hash values. If the query string contains something like "WHERE id > @msg_id", then the params must contain something like :msg_id => 1.

    Ruby types are mapped to Spanner types as follows:

    Spanner Ruby Notes
    BOOL true/false
    INT64 Integer
    FLOAT64 Float
    STRING String
    DATE Date
    TIMESTAMP Time, DateTime
    BYTES File, IO, StringIO, or similar
    ARRAY Array Nested arrays are not supported.
    STRUCT Hash, Data

    See Data types.

    See Data Types - Constructing a STRUCT.

  • types (Hash) (defaults to: nil)

    Types of the SQL parameters in params. It is not always possible for Cloud Spanner to infer the right SQL type from a value in params. In these cases, the types hash can be used to specify the exact SQL type for some or all of the SQL query parameters.

    The keys of the hash should be query string parameter placeholders, minus the "@". The values of the hash should be Cloud Spanner type codes from the following list:

    • :BOOL
    • :BYTES
    • :DATE
    • :FLOAT64
    • :INT64
    • :STRING
    • :TIMESTAMP
    • Array - Lists are specified by providing the type code in an array. For example, an array of integers are specified as [:INT64].
    • Fields - Nested Structs are specified by providing a Fields object.

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# File 'lib/google/cloud/spanner/batch_update.rb', line 138

def batch_update sql, params: nil, types: nil
  @statements << Statement.new(sql, params: params, types: types)
  true
end