Notes
SQLSTATE values: Any valid SQLSTATE value can be
used in the SIGNAL statement. However, it is recommended that programmers
define new SQLSTATEs based on ranges reserved for applications. This prevents
the unintentional use of an SQLSTATE value that might be defined by the database
manager in a future release.
SQLSTATE values are comprised of a two-character class code value, followed
by a three-character subclass code value. Class code values represent classes
of successful and unsuccessful execution conditions.
- SQLSTATE classes that begin with the characters '7' through '9' or 'I'
through 'Z' may be defined. Within these classes, any subclass may be defined.
- SQLSTATE classes that begin with the characters '0' through '6' or 'A'
through 'H' are reserved for the database manager. Within these classes,
subclasses that begin with the characters '0' through 'H' are reserved for
the database manager. Subclasses that begin with the characters 'I' through
'Z' may be defined.
For more information about SQLSTATEs, see the SQL Messages
and Codes book in the iSeries Information Center.
Assignment: When the SIGNAL statement is executed,
the value of each of the specified string-constants, SQL-parameter-names, and SQL-variable-names is assigned (using storage assignment) to the corresponding condition-information-item. For details on the assignment rules, see Assignments and comparisons. For details on the maximum length of specific condition-information-items, see GET DIAGNOSTICS.
Processing a SIGNAL statement: When a SIGNAL statement
is issued, the SQLCODE returned in the SQLCA is based on the SQLSTATE value
as follows:
- If the specified SQLSTATE class is either '01' or '02', a warning or not
found is signalled and the SQLCODE is set to +438.
- Otherwise, an exception is signalled and the SQLCODE is set to -438.
If the SQLSTATE or condition indicates that an exception (SQLSTATE class
other than '01' or '02') is signalled,
- If a handler exists in the same compound statement as the SIGNAL statement,
and the compound statement contains a handler for SQLEXCEPTION or the specified
SQLSTATE or condition; the exception is handled and control is transferred
to that handler.
- If the compound-statement is nested
and an outer level compound-statement has a handler
for SQLEXCEPTION or the specified SQLSTATE or condition; the exception is
handled and control is transferred to that handler.
- Otherwise, the exception is not handled and control is immediately returned
to the end of the compound statement.
If the SQLSTATE or condition indicates that a warning (SQLSTATE class '01')
or not found (SQLSTATE class '02') is signalled,
- If a handler exists in the same compound statement as the SIGNAL statement,
and the compound statement contains a handler for SQLWARNING (if the SQLSTATE
class is '01'), NOT FOUND (if the SQLSTATE class is '02'), or the specified
SQLSTATE or condition; the warning or not found condition is handled and control
is transferred to that handler.
- If the compound-statement is nested and an outer
level compound statement contains a handler for SQLWARNING (if the SQLSTATE
class is '01'), NOT FOUND (if the SQLSTATE class is '02'), or the specified
SQLSTATE or condition; the warning or not found condition is handled and the
exception is handled and control is returned to that handler.
- Otherwise, the warning is not handled and processing continues with the
next statement.
Affects on the diagnostic area: The SIGNAL
statement starts with a clear diagnostics area and sets the RETURNED_SQLSTATE
to reflect the SQLSTATE or condition name specified.
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