Variable default values
Variables get a default value when defined.
By default, variables are initialized to a value depending on the variable data type.
For example, when defining an 
INTEGER variable, it gets zero as default value,
while a DECIMAL variable is set to
NULL:MAIN
    DEFINE v1 INTEGER, v2 DECIMAL(10,2)
    DISPLAY v1  -- Shows "0"
    DISPLAY NVL(v2,"null") -- Shows "null"
END MAINThe next table lists default initialization values for each primitive data type:
| Data type | Default Value | 
|---|---|
CHAR | 
NULL | 
VARCHAR | 
NULL | 
STRING | 
NULL | 
BIGINT | 
Zero | 
INTEGER | 
Zero | 
SMALLINT | 
Zero | 
TINYINT | 
Zero | 
BOOLEAN | 
FALSE | 
FLOAT | 
Zero | 
SMALLFLOAT | 
Zero | 
DECIMAL | 
NULL | 
MONEY | 
NULL | 
DATE | 
1899-12-31 (= Zero in number of days) | 
DATETIME | 
NULL | 
INTERVAL | 
NULL | 
TEXT | 
NULL, must use LOCATE | 
BYTE | 
NULL, must use LOCATE |