Print SQL Connector

Sink

The Print connector allows for writing every row to the standard output or standard error stream.

It is designed for:

  • Easy test for streaming job.
  • Very useful in production debugging.

Four possible format options:

PrintCondition1Condition2
PRINT_IDENTIFIER:taskId> output
PRINT_IDENTIFIER providedparallelism > 1
PRINT_IDENTIFIER> output
PRINT_IDENTIFIER providedparallelism == 1
taskId> output
no PRINT_IDENTIFIER providedparallelism > 1
output
no PRINT_IDENTIFIER providedparallelism == 1

The output string format is “$row_kind(f0,f1,f2…)”, row_kind is the short string of RowKind, example is: “+I(1,1)”.

The Print connector is built-in.

Attention Print sinks print records in runtime tasks, you need to observe the task log.

How to create a Print table

  1. CREATE TABLE print_table (
  2.  f0 INT,
  3.  f1 INT,
  4.  f2 STRING,
  5.  f3 DOUBLE
  6. ) WITH (
  7.  'connector' = 'print'
  8. )

Alternatively, it may be based on an existing schema using the LIKE Clause.

  1. CREATE TABLE print_table WITH ('connector' = 'print')
  2. LIKE source_table (EXCLUDING ALL)

Connector Options

OptionRequiredDefaultTypeDescription
connector
required(none)StringSpecify what connector to use, here should be ‘print’.
print-identifier
optional(none)StringMessage that identify print and is prefixed to the output of the value.
standard-error
optionalfalseBooleanTrue, if the format should print to standard error instead of standard out.