spanner/v1.3.0

• Query options:
  • Adds the support of providing query options (optimizer version) via
    three ways (precedence follows the order):
    client-level < environment variables < query-level. The environment
    variable is set by "SPANNER_OPTIMIZER_VERSION".
• Connection pooling:
  • Use the new connection pooling in gRPC. This change deprecates
    ClientConfig.numChannels and users should move to
    WithGRPCConnectionPool(numChannels) at their earliest convenience.
    Example:

    // numChannels (deprecated):
    err, client := NewClientWithConfig(ctx, database, ClientConfig{NumChannels: 8})
    
    // gRPC connection pool:
    err, client := NewClientWithConfig(ctx, database, ClientConfig{}, option.WithGRPCConnectionPool(8))

• Error handling:
  • Do not rollback after failed commit.
  • Return TransactionOutcomeUnknownError if a DEADLINE_EXCEEDED or CANCELED
    error occurs while a COMMIT request is in flight.
• spansql:
  • Added support for IN expressions and OFFSET clauses.
  • Fixed parsing of table constraints.
  • Added support for foreign key constraints in ALTER TABLE and CREATE TABLE.
  • Added support for GROUP BY clauses.
• spannertest:
  • Added support for IN expressions and OFFSET clauses.
  • Added support for GROUP BY clauses.
  • Fixed data race in query execution.
  • No longer rejects reads specifying an index to use.
  • Return last commit timestamp as read timestamp when requested.
  • Evaluate add, subtract, multiply, divide, unary
    negation, unary not, bitwise and/xor/or operations, as well as reporting
    column types for expressions involving any possible arithmetic
    operator.arithmetic expressions.
  • Fixed handling of descending primary keys.
• Misc:
  • Change default healthcheck interval to 30 mins to reduce the GetSession
    calls made to the backend.
  • Add marshal/unmarshal json for nullable types to support NullString,
    NullInt64, NullFloat64, NullBool, NullTime, NullDate.
  • Use ResourceInfo to extract error.
  • Extract retry info from status.