To declare an lvarchar host variable for a character
column (CHAR, VARCHAR, or LVARCHAR), use the lvarchar keyword
as the variable data type.
The following syntax shows the lvarchar keyword
as the variable data type.
(explicit id )
lvarchar
{
| variable name[variable size] | *variable
name }
;
Element
Purpose
Restrictions
variable name
Name of an lvarchar variable of a specified
size
None
variable size
Number of bytes to allocate for an lvarchar variable
of specified size
Integer value can be 1 - 32,768 (32 KB).
*variable name
Name of an lvarchar pointer variable for
data of unspecified length
Not equivalent to a C char pointer (char *). Points
to an internal ESQL/C representation for this type. You must use the ifx_var() functions
to manipulate data.
The following figure shows declarations for three lvarchar variables
that hold values for LVARCHAR columns.Figure 1. Sample lvarchar host variables
EXEC SQL BEGIN DECLARE SECTION;
lvarchar *a_polygon;
lvarchar circle1[CIRCLESZ], circle2[CIRCLESZ];
EXEC SQL END DECLARE SECTION;
Important: To declare a lvarchar host variable
for the external format of an opaque data type, use the syntax described
in Declare lvarchar host variables.