
Lexical Elements of the SQL Language  SQL Language in 602SQL  Database Tables 
Data type specifies the set of possible values for a table column, variable, routine parameter or a function value. These types are available in 602SQL:
type ::= character_string [language_and_charset]  binary_object  bit_string  accurate_number_type
 approximate_number_type  BOOLEAN  DATE  TIME [WITH TIME ZONE]  TIMESTAMP [WITH TIME ZONE]
 domain_identifier
character_string ::= CHAR [( length )]  CHAR VARYING ( length )  VARCHAR ( length )  NCHAR [( length )]
 NCHAR VARYING ( length )  CLOB [( length )]  NCLOB [( length )]
binary_object ::= BLOB [( length )]
bit_string ::= BINARY ( length )  VARBINARY ( length )  BIT [( length )]  BIT VARYING ( length )
accurate_number_type ::= INTEGER  SMALLINT  TINYINT  BIGINT  DECIMAL [( precision [, decim ] )]
 NUMERIC [( precision [, decim ] )]
approximate_number_type ::= REAL  DOUBLE PRECISION  FLOAT [( precision )]
Without changing a meaning you can use INT instead of INTEGER, DEC instead of DECIMAL, CHARACTER instead of CHAR, NATIONAL CHAR or NATIONAL CHARACTER instead of NCHAR, CHAR LARGE OBJECT or CHARACTER LARGE OBJECT instead of CLOB and BINARY LARGE OBJECT instead of BLOB.
You can also use LONG VARCHAR instead of CLOB, LONG VARBINARY instead of BLOB and VARBINARY instead of BIT VARYING in order to maintain compatibility with ODBC.
Internal ("physical") data types used by a client program correspond with the SQL types, when the client sends or reads data. The following table describes the correspondence between the two type sets. The third column contains the constants used for physical types description.
SQL Type Description  Internal Representation  Designation  Number 
CHAR  one character  ATT_CHAR  2 
CHAR(n), CHAR VARYING(n), VARCHAR(n), for n<=4090  string character up to length n  ATT_STRING  7 
NCHAR(n), NCHAR VARYING(n), for n<=2045  Unicode character string up to length n  ATT_STRING  7 
CLOB, CLOB(n)  character string of unlimited length  ATT_TEXT  20 
NCLOB, NCLOB(n)  Unicode character string of unlimited length  ATT_TEXT  20 
BLOB, BLOB(n)  order of bytes  ATT_NOSPEC  21 
BINARY(n) for n<=4090  order of bytes up to length n  ATT_BINARY  10 
BIT, BIT(1), BOOLEAN  boolean values TRUE, FALSE or UNKNOWN  ATT_BOOLEAN  1 
BIT(n), BIT VARYING(n) for 1<n<=8*4090  order of (n1) / 8 + 1 bytes  ATT_BINARY  10 
INTEGER  4byte integer number  ATT_INT32  4 
SMALLINT  2byte integer number  ATT_INT16  3 
TINYINT  1byte integer number  ATT_INT8  45 
BIGINT  8byte integer number  ATT_INT64  46 
DECIMAL(n, d), NUMERIC(n, d) for n <= 2  1byte number with a scale d  ATT_INT8  45 
DECIMAL(n, d), NUMERIC(n, d) for 2 < n <= 4  2byte number with a scale d  ATT_INT16  3 
DECIMAL(n, d), NUMERIC(n, d) for 4 < n <= 9  4byte number with a scale d  ATT_INT32  4 
DECIMAL(n, d), NUMERIC(n, d) for n > 9  8byte number with a scale d  ATT_INT64  46 
REAL, DOUBLE PRECISION, FLOAT, FLOAT(n)  8byte real number  ATT_FLOAT  6 
DATE  date as a 4byte number  ATT_DATE  11 
TIME, TIME WITH TIME ZONE  time as a 4byte number  ATT_TIME  12 
TIMESTAMP, TIMESTAMP WITH TIME ZONE  date and time as a 4byte number  ATT_TIMESTAMP  13 
The NULL value belongs to each type. It's equivalent to the UNKNOWN value for BOOLEAN type, equivalent to the empty string for BLOB and string character types and equivalent to the string of zeros for binary strings. It's different from any other possible values for the other types.
Variances from Intermediate Level to the Entry Level
Variances from Intermediate to the Full Level
SQL Properties in 602SQL Defined by Implementation
Operating System Requirements
Full support for Unicode and 8bit strings in a nonWindows coding is available only in Windows 2000 and XP. The charset support depends on the system configuration for Linux systems  ISO charsets are usually supported, Windows code pages are usually not supported.
List of topics:
Lexical Elements of the SQL Language  SQL Language in 602SQL  Database Tables 