Impala - Query Language Basics
Impala Data types
The following table describes the Impala data types.
| Sr.No |
Data Type & Description |
| 1 |
BIGINT
This datatype stores numerical values and the range of this data type is -9223372036854775808 to 9223372036854775807. This datatype is used in create table and alter table statements.
|
| 2 |
BOOLEAN
This data type stores only true or false values and it is used in the column definition of create table statement.
|
| 3 |
CHAR
This data type is a fixed length storage, it is padded with spaces, you can store up to the maximum length of 255.
|
| 4 |
DECIMAL
This data type is used to store decimal values and it is used in create table and alter table statements.
|
| 5 |
DOUBLE
This data type is used to store the floating point values in the range of positive or negative 4.94065645841246544e-324d -1.79769313486231570e+308.
|
| 6 |
FLOAT
This data type is used to store single precision floating value datatypes in the range of positive or negative 1.40129846432481707e-45 .. 3.40282346638528860e+38.
|
| 7 |
INT
This data type is used to store 4-byte integer up to the range of -2147483648 to 2147483647.
|
| 8 |
SMALLINT
This data type is used to store 2-byte integer up to the range of -32768 to 32767.
|
| 9 |
STRING
This is used to store string values.
|
| 10 |
TIMESTAMP
This data type is used to represent a point in a time.
|
| 11 |
TINYINT
This data type is used to store 1-byte integer value up to the range of -128 to 127.
|
| 12 |
VARCHAR
This data type is used to store variable length character up to the maximum length 65,535.
|
| 13 |
ARRAY
This is a complex data type and it is used to store variable number of ordered elements.
|
| 14 |
Map
This is a complex data type and it is used to store variable number of key-value pairs.
|
| 15 |
Struct
This is a complex data type and used to represent multiple fields of a single item.
|
Comments in Impala
Comments in Impala are similar to those in SQL.In general we have two types of comments in programming languages namely Single-line Comments and Multiline Comments.
Single-line comments − Every single line that is followed by "—" is considered as a comment in Impala. Following is an example of a single-line comments in Impala.
-- Hello welcome to tutorials point.
Multiline comments − All the lines between /* and */ are considered as multiline comments in Impala. Following is an example of a multiline comments in Impala.
/*
Hi this is an example
Of multiline comments in Impala
*/
The operators in Impala are similar to those in SQL. Refer our SQL tutorial by clicking the following link sql-operators.
