Application Development
Table API & SQL
SQL
SHOW Statements
SHOW Statements
SHOW statements are used to list all catalogs, or list all databases in the current catalog, or list all tables/views in the current catalog and the current database, or show current catalog and database, or list all functions including temp system functions, system functions, temp catalog functions and catalog functions in the current catalog and the current database.
Flink SQL supports the following SHOW statements for now:
SHOW CATALOGS
SHOW CURRENT CATALOG
SHOW DATABASES
SHOW CURRENT DATABASE
SHOW TABLES
SHOW VIEWS
SHOW FUNCTIONS
Run a SHOW statement
SHOW statements can be executed with the executeSql()
method of the TableEnvironment
. The executeSql()
method returns objects for a successful SHOW operation, otherwise will throw an exception.
The following examples show how to run a SHOW statement in TableEnvironment
.
SHOW statements can be executed with the execute_sql()
method of the TableEnvironment
. The execute_sql()
method returns objects for a successful SHOW operation, otherwise will throw an exception.
The following examples show how to run a SHOW statement in TableEnvironment
.
SHOW statements can be executed in SQL CLI .
The following examples show how to run a SHOW statement in SQL CLI.
StreamExecutionEnvironment env = StreamExecutionEnvironment . getExecutionEnvironment ();
StreamTableEnvironment tEnv = StreamTableEnvironment . create ( env );
// show catalogs
tEnv . executeSql ( "SHOW CATALOGS" ). print ();
// +-----------------+
// | catalog name |
// +-----------------+
// | default_catalog |
// +-----------------+
// show current catalog
tEnv . executeSql ( "SHOW CURRENT CATALOG" ). print ();
// +----------------------+
// | current catalog name |
// +----------------------+
// | default_catalog |
// +----------------------+
// show databases
tEnv . executeSql ( "SHOW DATABASES" ). print ();
// +------------------+
// | database name |
// +------------------+
// | default_database |
// +------------------+
// show current database
tEnv . executeSql ( "SHOW CURRENT DATABASE" ). print ();
// +-----------------------+
// | current database name |
// +-----------------------+
// | default_database |
// +-----------------------+
// create a table
tEnv . executeSql ( "CREATE TABLE my_table (...) WITH (...)" );
// show tables
tEnv . executeSql ( "SHOW TABLES" ). print ();
// +------------+
// | table name |
// +------------+
// | my_table |
// +------------+
// create a view
tEnv . executeSql ( "CREATE VIEW my_view AS ..." );
// show views
tEnv . executeSql ( "SHOW VIEWS" ). print ();
// +-----------+
// | view name |
// +-----------+
// | my_view |
// +-----------+
// show functions
tEnv . executeSql ( "SHOW FUNCTIONS" ). print ();
// +---------------+
// | function name |
// +---------------+
// | mod |
// | sha256 |
// | ... |
// +---------------+
val env = StreamExecutionEnvironment . getExecutionEnvironment ()
val tEnv = StreamTableEnvironment . create ( env )
// show catalogs
tEnv . executeSql ( "SHOW CATALOGS" ). print ()
// +-----------------+
// | catalog name |
// +-----------------+
// | default_catalog |
// +-----------------+
// show databases
tEnv . executeSql ( "SHOW DATABASES" ). print ()
// +------------------+
// | database name |
// +------------------+
// | default_database |
// +------------------+
// create a table
tEnv . executeSql ( "CREATE TABLE my_table (...) WITH (...)" )
// show tables
tEnv . executeSql ( "SHOW TABLES" ). print ()
// +------------+
// | table name |
// +------------+
// | my_table |
// +------------+
// create a view
tEnv . executeSql ( "CREATE VIEW my_view AS ..." )
// show views
tEnv . executeSql ( "SHOW VIEWS" ). print ()
// +-----------+
// | view name |
// +-----------+
// | my_view |
// +-----------+
// show functions
tEnv . executeSql ( "SHOW FUNCTIONS" ). print ()
// +---------------+
// | function name |
// +---------------+
// | mod |
// | sha256 |
// | ... |
// +---------------+
settings = EnvironmentSettings . new_instance ()...
table_env = StreamTableEnvironment . create ( env , settings )
# show catalogs
table_env . execute_sql ( "SHOW CATALOGS" ). print ()
# +-----------------+
# | catalog name |
# +-----------------+
# | default_catalog |
# +-----------------+
# show databases
table_env . execute_sql ( "SHOW DATABASES" ). print ()
# +------------------+
# | database name |
# +------------------+
# | default_database |
# +------------------+
# create a table
table_env . execute_sql ( "CREATE TABLE my_table (...) WITH (...)" )
# show tables
table_env . execute_sql ( "SHOW TABLES" ). print ()
# +------------+
# | table name |
# +------------+
# | my_table |
# +------------+
# create a view
table_env . execute_sql ( "CREATE VIEW my_view AS ..." )
# show views
table_env . execute_sql ( "SHOW VIEWS" ). print ()
# +-----------+
# | view name |
# +-----------+
# | my_view |
# +-----------+
# show functions
table_env . execute_sql ( "SHOW FUNCTIONS" ). print ()
# +---------------+
# | function name |
# +---------------+
# | mod |
# | sha256 |
# | ... |
# +---------------+
Flink SQL > SHOW CATALOGS ;
default_catalog
Flink SQL > SHOW DATABASES ;
default_database
Flink SQL > CREATE TABLE my_table (...) WITH (...);
[ INFO ] Table has been created .
Flink SQL > SHOW TABLES ;
my_table
Flink SQL > CREATE VIEW my_view AS ...;
[ INFO ] View has been created .
Flink SQL > SHOW VIEWS ;
my_view
Flink SQL > SHOW FUNCTIONS ;
mod
sha256
...
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SHOW CATALOGS
SHOW CATALOGS
Show all catalogs.
SHOW CURRENT CATALOG
SHOW CURRENT CATALOG
Show current catalog.
SHOW DATABASES
SHOW DATABASES
Show all databases in the current catalog.
SHOW CURRENT DATABASE
SHOW CURRENT DATABASE
Show current database.
SHOW TABLES
SHOW TABLES
Show all tables in the current catalog and the current database.
SHOW VIEWS
SHOW VIEWS
Show all views in the current catalog and the current database.
SHOW FUNCTIONS
SHOW FUNCTIONS
Show all functions including temp system functions, system functions, temp catalog functions and catalog functions in the current catalog and current database.