Module streaming_ddl 

Streaming DDL (CREATE SOURCE/SINK) translator SQL DDL to Streaming API translation.

This module translates parsed SQL CREATE SOURCE/SINK statements into typed streaming definitions that can be used to configure the runtime.

Supported Syntax

-- In-memory streaming source
CREATE SOURCE trades (
    symbol VARCHAR NOT NULL,
    price DOUBLE NOT NULL,
    quantity BIGINT NOT NULL,
    ts TIMESTAMP NOT NULL,
    WATERMARK FOR ts AS ts - INTERVAL '100' MILLISECONDS
) WITH (
    buffer_size = 131072,
    backpressure = 'block'
);

-- In-memory streaming sink
CREATE SINK trade_aggregates AS
    SELECT * FROM trade_stats
WITH (
    buffer_size = 65536
);

Validation

• Rejects channel = ... option (channel type is auto-derived)
• Validates buffer_size is within bounds
• Validates backpressure strategy names
• Validates wait_strategy names

Structs

ColumnDefinition

Column definition for a streaming source.

SinkDefinition

A validated streaming sink definition.

SourceConfigOptions

Configuration options for a streaming source.

SourceDefinition

A validated streaming source definition.

WatermarkSpec

Watermark specification for a source.

Enums

BackpressureStrategy

Backpressure strategy for streaming channels.

WaitStrategy

Wait strategy for streaming consumers.

Constants

DEFAULT_BUFFER_SIZE

Default buffer size for streaming channels.

MAX_BUFFER_SIZE

Maximum buffer size for streaming channels.

MIN_BUFFER_SIZE

Minimum buffer size for streaming channels.

Functions

sql_type_to_arrow

Converts SQL data type to Arrow data type.

translate_create_sink

Translates a CREATE SINK statement to a typed SinkDefinition.

translate_create_source

Translates a CREATE SOURCE statement to a typed SourceDefinition.