USE Statements

    Java

    USE statements can be executed with the method of the TableEnvironment. The executeSql() method returns ‘OK’ for a successful USE operation, otherwise will throw an exception.

    The following examples show how to run a USE statement in TableEnvironment.

    Scala

    USE statements can be executed with the executeSql() method of the TableEnvironment. The executeSql() method returns ‘OK’ for a successful USE operation, otherwise will throw an exception.

    Python

    USE statements can be executed with the execute_sql() method of the TableEnvironment. The execute_sql() method returns ‘OK’ for a successful USE operation, otherwise will throw an exception.

    The following examples show how to run a USE statement in TableEnvironment.

    SQL CLI

    USE statements can be executed in SQL CLI.

    Java

    Scala

    1. val env = StreamExecutionEnvironment.getExecutionEnvironment()
    2. val tEnv = StreamTableEnvironment.create(env)
    4. // create a catalog
    5. tEnv.executeSql("CREATE CATALOG cat1 WITH (...)")
    6. tEnv.executeSql("SHOW CATALOGS").print()
    7. // +-----------------+
    8. // |    catalog name |
    9. // +-----------------+
    10. // | default_catalog |
    11. // | cat1            |
    12. // +-----------------+
    14. // change default catalog
    15. tEnv.executeSql("USE CATALOG cat1")
    17. tEnv.executeSql("SHOW DATABASES").print()
    18. // databases are empty
    20. // | database name |
    21. // +---------------+
    23. // create a database
    24. tEnv.executeSql("CREATE DATABASE db1 WITH (...)")
    25. tEnv.executeSql("SHOW DATABASES").print()
    26. // +---------------+
    27. // | database name |
    28. // +---------------+
    29. // |        db1    |
    30. // +---------------+
    32. // change default database
    33. tEnv.executeSql("USE db1")
    35. // change module resolution order and enabled status
    36. tEnv.executeSql("USE MODULES hive")
    37. tEnv.executeSql("SHOW FULL MODULES").print()
    38. // +-------------+-------+
    39. // | module name |  used |
    40. // +-------------+-------+
    41. // |        hive |  true |
    42. // |        core | false |
    43. // +-------------+-------+

    Python

    SQL CLI

    1. Flink SQL> CREATE CATALOG cat1 WITH (...);
    2. [INFO] Catalog has been created.
    5. cat1
    7. Flink SQL> USE CATALOG cat1;
    9. Flink SQL> SHOW DATABASES;
    11. Flink SQL> CREATE DATABASE db1 WITH (...);
    12. [INFO] Database has been created.
    14. Flink SQL> SHOW DATABASES;
    15. db1
    17. Flink SQL> USE db1;
    19. Flink SQL> USE MODULES hive;
    20. [INFO] Use modules succeeded!
    21. Flink SQL> SHOW FULL MODULES;
    22. +-------------+-------+
    23. | module name |  used |
    24. +-------------+-------+
    25. |        hive |  true |
    26. |        core | false |
    27. +-------------+-------+
    28. 2 rows in set

    Set the current catalog. All subsequent commands that do not explicitly specify a catalog will use this one. If the provided catalog does not exist, an exception is thrown. The default current catalog is default_catalog.

      Set the current database. All subsequent commands that do not explicitly specify a database will use this one. If the provided database does not exist, an exception is thrown. The default current database is default_database.