The following table shows how the Impala data types are mapped to the standard JDBC data types.

Table 1. Impala Data Types
Impala JDBC
Array1 ARRAY
Bigint BIGINT
Boolean BOOLEAN
Char CHAR
Decimal DECIMAL
Double DOUBLE
Float REAL
Int INTEGER
Smallint SMALLINT
String2 VARCHAR or LONGVARCHAR3
Timestamp TIMESTAMP
Tinyint TINYINT
Varchar VARCHAR
1 Supports only DQL with Array data type
2 Maximum of 2 GB
3 If the StringDescribeType connection property is set to varchar (the default), the String data type maps to VARCHAR. If StringDescribeType is set to longvarchar, String maps to LONGVARCHAR.