Meta functions

all_tables

all_tables() returns a list of tables.

Arguments

• all_tables() does not require arguments.

Description

Returns all tables in the database.

Return value

Returns a table.

Examples:

• Get all tables in the database

all_tables();

tableName
table1
table2
...

• Get all tables in the database that match 'sales'

all_tables() WHERE tableName ~= 'sales';

tableName
sales-north
sales-west
sales-east
sales-south

• Get all tables in reverse alphabetical order

all_tables() ORDER BY tableName DESC;

tableName
table_n
table_n-1
table_n-2
...

table_columns

table_columns('tableName') returns the schema of a table

Arguments

• tableName is the name of an existing table as a string

Description

Returns the schema of the target table.

Return value

Returns a table with two columns:

• columnName - name of the available columns in the table
• columnType - type of the column

Examples:

• Get all columns in the table

table_columns('myTable')

columnName	columnType
TS	TIMESTAMP
Name	STRING
Age	INT
Sex	SYMBOL
Grade	DOUBLE
...	...

• Get all columns in the database that match the name 'sales'

SELECT columnName FROM table_columns('myTable') WHERE columnName ~= 'sales';

columnName
sales-north
sales-west
sales-east
sales-south

• Get the count of column types

SELECT columnType, count() FROM table_columns('wthr');

columnType	count
INT	4
DOUBLE	8
SYMBOL	2