INFORMIX
IBM Informix Embedded SQLJ User's Guide
Chapter 4: The Embedded SQLJ Language
Contents Index

SQL and Java Type Mappings

When you retrieve data from a database into an iterator object (see "Handling Result Sets") or into a host variable, you must use Java types that are compatible with the SQL types. The following table shows valid conversions from SQL types to Java types.

SQL Type Java Type

BLOB

byte[]

BOOLEAN

boolean

BYTE

byte[]

CHAR, CHARACTER

String

CHARACTER VARYING

String

CLOB

byte[]

DATE

java.sql.Date

DATETIME

java.sql.Timestamp

DECIMAL, NUMERIC, DEC

java.math.BigDecimal

FLOAT, DOUBLE PRECISION

double

INT8

long

INTEGER, INT

int

INTERVAL

IfxIntervalDF, IfxIntervalYM *

LVARCHAR

String

MONEY

java.math.BigDecimal

NCHAR, NVARCHAR

String

SERIAL

int

SERIAL8

long

SMALLFLOAT

double

SMALLINT

short

TEXT

String

VARCHAR

String

* IfxIntervalYM and IfxIntervalDF are Informix extensions to JDBC 2.0.

You must also use compatible Java types for host variables that are arguments to SQL operations. This table shows valid conversions from Java types to SQL types.

Java Type SQL Type

java.math.BigDecimal

DECIMAL

boolean

BOOLEAN

byte[]

BYTE

java.sql.Date

DATE

double

FLOAT

float

SMALLFLOAT

int

INT

long

INT8

short

SMALLINT

String

CHAR

java.sql.Time

DATETIME

java.sql.Timestamp

DATETIME

com.informix.jdbc.IfxIntervalDF

INTERVAL

com.informix.jdbc.IfxIntervalYM

INTERVAL

Important: Unlike other host languages (for example, C), Java allows null data. Therefore, you do not need to use null indicator variables with Embedded SQLJ. The Java null value is equivalent to the SQL NULL value.




IBM Informix Embedded SQLJ User's Guide, Version 1.0
Copyright © 1999, IBM Corporation. All rights reserved.