class %SQL.StatementMetadata
extends %RegisteredObject
Metadata describes the statement interface. The statement metadata contains the type of statement, the number of
columns defined by the statement and the metadata for each column. Statement columns are of three primary types:
result columns, parameters, and the return value. There is also a distinction between the metadata available for a
prepared statement and for a statement that has been executed since not all statement results are known at prepare
time. For all statement types except CALL, the statement metadata is all available at prepare time. CALL statement metadata
that is available at prepare time includes the metadata from the statement itself and that metadata is not to be confused
with the metadata defined by the SQL routine that is called. Each routine defines a formal interface that consists of an
optional return value and option input, input-output and output parameters. An SQL routine might also return a single
preplanned result set. That metadata is available at prepare time and it consists of some number of columns of type
SQLRESULTCOL. An SQL routine might also declare that it returns some dynamic result sets, the metadata for which is not
available until after the statement is executed and the result sets bound dynamic cursors.
• property columnCount
as %Integer;
The number of columns defined as SQLRESULTCOL that are returned by executing this statement.
This is the same as columns.Count().
• property columnIndex
as %String(MAXLEN="") [ MultiDimensional ];
Index on column names and column number.
• property columns
as list of %SQL.StatementColumn;
columns is a collection of StatementColumn objects. Each StatementColumn object
contains the metadata a column defined by the statement as an SQLRESULTCOL column type.
• property formalParameters
as list of %SQL.StatementParameter;
formalParameters is a collection of '?' parameters found in the prepared statement.
It may differ from the parameters collection if literal replacement occurred. This
property is mainly for internal use and metadata reporting. It is not meant to be used
for the statement descriptor.
• property interface
as %Integer;
interface is an integer value indicating the routine interface:
-2 - Return value, dynamic cursors returned (zero, one or more)
-1 - No return value, dynamic cursors returned (RETURNRESULTSETS, zero one or more)
0 - No return value, no dynamic cursors (NOT RETURNRESULTSETS, aka "function" procedure although a function should return a value (interface = 2))
1 - No return value, one pre-planned result set (AKA "query" procedure)
2 - Return value, no dynamic cursors (NOT RETURNRESULTSETS)
• property objects
as list of %SQL.StatementObject;
A collection of StatementObject objects representing the columns that are object values.
• property parameterCount
as %Integer;
The number of parameters defined in this statement. This is the same as
parameters.Count().
• property parameters
as list of %SQL.StatementParameter;
The parameters collection contains the metadata for each actual parameter
contained in the source statement. ..parameters.Count() is equivalent to the
number of '?' parameters found in the source statement and the list position
corresponds to the ordinal position of the '?' in the source statement.
• property statementType
as %Integer;
An integer representing the type of statement.
1 - SELECT
2 - INSERT
3 - UPDATE
4 - DELETE
5 - COMMIT
6 - ROLLBACK
7 - GRANT
8 - REVOKE
9 - CREATE TABLE
10 - ALTER TABLE
11 - DROP TABLE
12 - CREATE VIEW
13 - ALTER VIEW
14 - DROP VIEW
15 - CREATE INDEX
16 - ALTER INDEX
17 - DROP INDEX
18 - CREATE ROLL
19 - DROP ROLL
20 - SET TRANSACTION
21 - START TRANSACTION
22 - %IN_TRANSACTION
23 - %BEGTRANS
24 - %INTRANS
25 - GET
26 - SET OPTION
27 - STATISTICS
28 - %CHECKPRIV
29 - CREATE USER
30 - ALTER USER
31 - DROP USER
32 - %CHECKPRIV
33 - GRANT
34 - REVOKE
35 - CREATE FUNCTION
36 - CREATE METHOD
37 - CREATE PROCEDURE
38 - CREATE QUERY
39 - DROP FUNCTION
40 - DROP METHOD
41 - DROP PROCEDURE
42 - DROP QUERY
43 - CREATE TRIGGER
44 - DROP TRIGGER
45 - CALL
46 - SAVEPOINT
47 - LOCK TABLE
48 - UNLOCK TABLE
• method %Display()
as %Status
Display metadata on the current device.
• classmethod %GenerateMetadata(ByRef pInfo As %Binary, pStatementType As %Integer = 0, ByRef pMetadata As %Binary, ByRef pParameters As %Binary = "", ByRef pObjects As %Binary, ByRef pActual As %List = "", ByRef pDynamic As %List = "")
as %Status
GenerateMetadata constructs the serialized metadata from the query processor's info array.
IF %protocol 41 and higher:
metadata = $lb()
1 - # of SELECT columns
2 - i:
1) Name
2) ODBC Type
3) Precision
4) Scale
5) NULLABLE (integer)
6) Column Label (same as Name)
7) Column Table Name
8) Column Schema Name
9) Column Qualifier Name - NULL
10) $Char(1)/$Char(0) string / $Extract position:
1) isAutoIncrement
2) isCaseSensitive
3) isCurrency
4) IsReadOnly
5) IsRowVersion
6) IsUnique
7) IsAliased
8) IsExpression
9) IsHidden
10) IsIdentity
11) IsKeyColumn
12) IsRowid // DPV3092
j - # of Parameters
j+1 - k:
1) ODBC Type
2) Precision
3) Scale
4) NULLABLE
5) colName
6) colType
IF %protocol less than 41:
metadata = $lb()
1 - # of SELECT columns
2 - i:
1) Name
2) ODBC Type
3) Precision
4) Scale
5) NULLABLE
6) Column Label (same as Name)
7) Column Table Name
8) Column Schema Name
9) Column Qualifier Name - NULL
j - # of Parameters
j+1 - k:
1) ODBC Type
2) Precision
3) Scale
4) NULLABLE
• method printMetadata(pMetadata As %CacheString)
as %Status
