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Column Types


IOMETE supports the following column types:

Type NameDescription
BOOLEANRepresents boolean values
BYTE, TINYINTRepresents 1-byte signed integer numbers. The range of numbers is from -128 to 127
SHORT, SMALLINTRepresents 2-byte signed integer numbers. The range of numbers is from -32768 to 32767
INT, INTEGERRepresents 4-byte signed integer numbers. The range of numbers is from -2147483648 to 2147483647
LONG, BIGINTRepresents 8-byte signed integer numbers. The range of numbers is from -9223372036854775808 to 9223372036854775807
FLOAT, REALRepresents 4-byte single-precision floating-point numbers
DOUBLERepresents 8-byte double-precision floating-point numbers
DATERepresents values comprising values of fields year, month, and day, without a time-zone
TIMESTAMPRepresents values comprising values of fields year, month, day, hour, minute, and second, with the session local time-zone. The timestamp value represents an absolute point in time
STRINGRepresents character string values
BINARYRepresents byte sequence values
DECIMAL, DEC, NUMERICRepresents arbitrary-precision signed decimal numbers. Backed internally by java.math.BigDecimal. A BigDecimal consists of an arbitrary precision integer unscaled value and a 32-bit integer scale
ARRAYRepresents values comprising a sequence of elements with the type of elementType
STRUCT<name1: type, ...>Represents values with the structure described by a sequence of name:type pairs
MAP<keytype, valuetype>Represents values comprising a set of key-value pairs. The data type of keys is described by keyType and the data type of values is described by valueType

Examples‚Äč


Bool type

CREATE TABLE IF NOT EXISTS bool_types (id INT, bool_col BOOLEAN) USING delta;

INSERT INTO bool_types VALUES (1, false);
INSERT INTO bool_types VALUES (2, true);
INSERT INTO bool_types VALUES (3, false);
INSERT INTO bool_types VALUES (4, true);
INSERT INTO bool_types VALUES (5, 0);
INSERT INTO bool_types VALUES (6, 1);
INSERT INTO bool_types VALUES (7, '');
INSERT INTO bool_types VALUES (8, 'some val');
INSERT INTO bool_types VALUES (null);

select * from bool_types order by id;

+-----+-----------+
| id | bool_col |
+-----+-----------+
| 1 | false |
| 2 | true |
| 3 | false |
| 4 | true |
| 5 | false |
| 6 | true |
| 7 | NULL |
| 8 | NULL |
+-----+-----------+

Integer types

CREATE TABLE IF NOT EXISTS integer_types (id INT, byte_col BYTE, short_col SHORT, int_col INT, long_col LONG) USING delta;

INSERT INTO integer_types VALUES (1, 1, 1, 1, 1);
--min numbers
INSERT INTO integer_types VALUES (2, -128, -32768, -2147483648, -9223372036854775808);
--max number
INSERT INTO integer_types VALUES (3, 127, 32767, 2147483647, 9223372036854775807);

INSERT INTO bool_types VALUES (2, true);
INSERT INTO bool_types VALUES (3, false);
INSERT INTO bool_types VALUES (4, true);
INSERT INTO bool_types VALUES (5, 0);
INSERT INTO bool_types VALUES (6, 1);
INSERT INTO bool_types VALUES (7, '');
INSERT INTO bool_types VALUES (8, 'some val');
INSERT INTO bool_types VALUES (null);


select * from integer_types order by id;

+-----+-----------+------------+--------------+-----------------------+
| id | byte_col | short_col | int_col | long_col |
+-----+-----------+------------+--------------+-----------------------+
| 1 | 1 | 1 | 1 | 1 |
| 2 | -128 | -32768 | -2147483648 | -9223372036854775808 |
| 3 | 127 | 32767 | 2147483647 | 9223372036854775807 |
+-----+-----------+------------+--------------+-----------------------+

Floating point numbers

CREATE TABLE IF NOT EXISTS floating_point_number_types (id INT, float_col FLOAT, double_col DOUBLE) USING delta;

INSERT INTO floating_point_number_types VALUES (1, 1, 1);
INSERT INTO floating_point_number_types VALUES (2, 1.12345, 1.12345);
-- Positive/Negative Infinity and NaN values
INSERT INTO floating_point_number_types VALUES (3, double('infinity'),double('infinity'));
INSERT INTO floating_point_number_types VALUES (4, double('-infinity'),double('-infinity'));
INSERT INTO floating_point_number_types VALUES (5, double('inf'), double('inf'));
INSERT INTO floating_point_number_types VALUES (6, double('-inf'), double('-inf'));
INSERT INTO floating_point_number_types VALUES (7, double('NaN'), double('NaN'));


select * from floating_point_number_types order by id;

+-----+------------+-------------+
| id | float_col | double_col |
+-----+------------+-------------+
| 1 | 1.0 | 1.0 |
| 2 | 1.12345 | 1.12345 |
| 3 | Infinity | Infinity |
| 4 | -Infinity | -Infinity |
| 5 | Infinity | Infinity |
| 6 | -Infinity | -Infinity |
| 7 | NaN | NaN |
+-----+------------+-------------+

Date types

CREATE TABLE IF NOT EXISTS date_types (id INT, date_col DATE, ts_col TIMESTAMP) USING delta;

INSERT INTO date_types VALUES (1, '2020-01-01', current_timestamp());
INSERT INTO date_types VALUES (2, '2020-01-31', current_timestamp());

select * from date_types order by id;

+-----+-------------+--------------------------+
| id | date_col | ts_col |
+-----+-------------+--------------------------+
| 1 | 2020-01-01 | 2021-01-03 14:22:01.913 |
| 2 | 2020-01-31 | 2021-01-03 14:23:41.7 |
+-----+-------------+--------------------------+

String type

CREATE TABLE IF NOT EXISTS str_type (id INT, str_col STRING) USING delta;

INSERT INTO str_type VALUES (1, 'Some text here');

select * from str_type order by id;

+-----+-----------------+
| id | str_col |
+-----+-----------------+
| 1 | Some text here |
+-----+-----------------+

Numeric type

-- NUMERIC(value, precision)
CREATE TABLE IF NOT EXISTS bigdecimal_type (id INT, numeric_col NUMERIC(10,5)) USING delta;

INSERT INTO bigdecimal_type VALUES (1, 123.1234);
--decimal point is rounded
INSERT INTO bigdecimal_type VALUES (2, 12345.123456);
-- This cannot be represented by BigDecimal. Unscaled value (12345612345) has more than 10 digits
--INSERT INTO bigdecimal_type3 VALUES (2, 123456.12345);

select * from bigdecimal_type order by id;

+-----+--------------+
| id | numeric_col |
+-----+--------------+
| 1 | 123.12340 |
| 2 | 12345.12346 |
+-----+--------------+

Array type

CREATE TABLE IF NOT EXISTS array_type (id INT, array_int_col ARRAY<INT>, array_str_col ARRAY<STRING>) USING delta;

INSERT INTO array_type VALUES (1, array(), array());
INSERT INTO array_type VALUES (2, array(1,2,3), array('one', 'two', 'three'));


select * from array_type order by id;

+-----+----------------+------------------------+
| id | array_int_col | array_str_col |
+-----+----------------+------------------------+
| 1 | [] | [] |
| 2 | [1,2,3] | ["one","two","three"] |
+-----+----------------+------------------------+

Struct type

CREATE TABLE IF NOT EXISTS struct_type (id INT, struct_col STRUCT<num:INT, txt: STRING>) USING delta;

INSERT INTO struct_type VALUES (1, struct(1, 'one'));
-- with names
INSERT INTO struct_type VALUES (2, named_struct("num", 1, "txt", 'one'));


select * from struct_type order by id;

+-----+------------------------+
| id | struct_col |
+-----+------------------------+
| 1 | {"num":1,"txt":"one"} |
| 2 | {"num":1,"txt":"one"} |
+-----+------------------------+

Map type

CREATE TABLE IF NOT EXISTS map_type (id INT, map_col MAP<INT, STRING>) USING delta;

INSERT INTO map_type VALUES (1, map(1, 'one', 2, 'two', 3, 'three'));


select * from map_type order by id;

+-----+------------------------------+
| id | map_col |
+-----+------------------------------+
| 1 | {1:"one",2:"two",3:"three"} |
+-----+------------------------------+