Queries #

StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);

// ingest a DataStream from an external source
DataStream<Tuple3<Long, String, Integer>> ds = env.addSource(...);

// SQL query with an inlined (unregistered) table
Table table = tableEnv.fromDataStream(ds, $("user"), $("product"), $("amount"));
Table result = tableEnv.sqlQuery(
  "SELECT SUM(amount) FROM " + table + " WHERE product LIKE '%Rubber%'");

// SQL query with a registered table
// register the DataStream as view "Orders"
tableEnv.createTemporaryView("Orders", ds, $("user"), $("product"), $("amount"));
// run a SQL query on the Table and retrieve the result as a new Table
Table result2 = tableEnv.sqlQuery(
  "SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%'");

// create and register a TableSink
final Schema schema = Schema.newBuilder()
    .column("product", DataTypes.STRING())
    .column("amount", DataTypes.INT())
    .build();

final TableDescriptor sinkDescriptor = TableDescriptor.forConnector("filesystem")
    .schema(schema)
    .option("path", "/path/to/file")    
    .format(FormatDescriptor.forFormat("csv")
        .option("field-delimiter", ",")
        .build())
    .build();

tableEnv.createTemporaryTable("RubberOrders", sinkDescriptor);

// run an INSERT SQL on the Table and emit the result to the TableSink
tableEnv.executeSql(
  "INSERT INTO RubberOrders SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%'");

val env = StreamExecutionEnvironment.getExecutionEnvironment
val tableEnv = StreamTableEnvironment.create(env)

// read a DataStream from an external source
val ds: DataStream[(Long, String, Integer)] = env.addSource(...)

// SQL query with an inlined (unregistered) table
val table = ds.toTable(tableEnv, $"user", $"product", $"amount")
val result = tableEnv.sqlQuery(
  s"SELECT SUM(amount) FROM $table WHERE product LIKE '%Rubber%'")

// SQL query with a registered table
// register the DataStream under the name "Orders"
tableEnv.createTemporaryView("Orders", ds, $"user", $"product", $"amount")
// run a SQL query on the Table and retrieve the result as a new Table
val result2 = tableEnv.sqlQuery(
  "SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%'")

// create and register a TableSink
val schema = Schema.newBuilder()
  .column("product", DataTypes.STRING())
  .column("amount", DataTypes.INT())
  .build()

val sinkDescriptor = TableDescriptor.forConnector("filesystem")
  .schema(schema)
  .format(FormatDescriptor.forFormat("csv")
    .option("field-delimiter", ",")
    .build())
  .build()

tableEnv.createTemporaryTable("RubberOrders", sinkDescriptor)

// run an INSERT SQL on the Table and emit the result to the TableSink
tableEnv.executeSql(
  "INSERT INTO RubberOrders SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%'")

env = StreamExecutionEnvironment.get_execution_environment()
table_env = StreamTableEnvironment.create(env)

# SQL query with an inlined (unregistered) table
# elements data type: BIGINT, STRING, BIGINT
table = table_env.from_elements(..., ['user', 'product', 'amount'])
result = table_env \
    .sql_query("SELECT SUM(amount) FROM %s WHERE product LIKE '%%Rubber%%'" % table)

# create and register a TableSink
schema = Schema.new_builder()
    .column("product", DataTypes.STRING())
    .column("amount", DataTypes.INT())
    .build()

sink_descriptor = TableDescriptor.for_connector("filesystem")
    .schema(schema)
    .format(FormatDescriptor.for_format("csv")
        .option("field-delimiter", ",")
        .build())
    .build()

t_env.create_temporary_table("RubberOrders", sink_descriptor)

# run an INSERT SQL on the Table and emit the result to the TableSink
table_env \
    .execute_sql("INSERT INTO RubberOrders SELECT product, amount FROM Orders WHERE product LIKE '%Rubber%'")

StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env, settings);

tableEnv.executeSql("CREATE TABLE Orders (`user` BIGINT, product STRING, amount INT) WITH (...)");

// execute SELECT statement
TableResult tableResult1 = tableEnv.executeSql("SELECT * FROM Orders");
// use try-with-resources statement to make sure the iterator will be closed automatically
try (CloseableIterator<Row> it = tableResult1.collect()) {
    while(it.hasNext()) {
        Row row = it.next();
        // handle row
    }
}

// execute Table
TableResult tableResult2 = tableEnv.sqlQuery("SELECT * FROM Orders").execute();
tableResult2.print();

val env = StreamExecutionEnvironment.getExecutionEnvironment()
val tableEnv = StreamTableEnvironment.create(env, settings)
// enable checkpointing
tableEnv.getConfig.set(
  CheckpointingOptions.CHECKPOINTING_MODE, CheckpointingMode.EXACTLY_ONCE)
tableEnv.getConfig.set(
  CheckpointingOptions.CHECKPOINTING_INTERVAL, Duration.ofSeconds(10))

tableEnv.executeSql("CREATE TABLE Orders (`user` BIGINT, product STRING, amount INT) WITH (...)")

// execute SELECT statement
val tableResult1 = tableEnv.executeSql("SELECT * FROM Orders")
val it = tableResult1.collect()
try while (it.hasNext) {
  val row = it.next
  // handle row
}
finally it.close() // close the iterator to avoid resource leak

// execute Table
val tableResult2 = tableEnv.sqlQuery("SELECT * FROM Orders").execute()
tableResult2.print()

env = StreamExecutionEnvironment.get_execution_environment()
table_env = StreamTableEnvironment.create(env, settings)
# enable checkpointing
table_env.get_config().set("execution.checkpointing.mode", "EXACTLY_ONCE")
table_env.get_config().set("execution.checkpointing.interval", "10s")

table_env.execute_sql("CREATE TABLE Orders (`user` BIGINT, product STRING, amount INT) WITH (...)")

# execute SELECT statement
table_result1 = table_env.execute_sql("SELECT * FROM Orders")
table_result1.print()

# execute Table
table_result2 = table_env.sql_query("SELECT * FROM Orders").execute()
table_result2.print()