JMS/XLA MapMessage Contents

A jakarta.jms.MapMessage instance for Jakarta JMS or javax.jms.MapMessage instance for JavaX JMS contains a set of typed name/value pairs corresponding to the fields in an XLA update header, which is published as the C structure ttXlaUpdateDesc_t.

The fields contained in a MapMessage instance depend on what type of update it is.

XLA Update Types

Each MapMessage instance returned by the JMS/XLA API contains at least one name/value pair, __TYPE (with 2 underscores), that identifies the type of update described in the message. The types are specified as integer values.

Table 6-1 lists the supported types.

Note:

As a convenience, you can use the constants defined in com.timesten.dataserver.jakartajmsxla.XLAConstants for Jakata JMS or com.timesten.dataserver.jmsxla.XlaConstants for JavaX JMS to compare against the integer types.

Table 6-1 XLA Update Types

Type	Description
`ADD_COLUMNS`	Indicates that columns have been added.
`COMMIT_FIELD`	This is the name of the field in a message that contains a commit.
`COMMIT_ONLY`	Indicates that a commit has occurred.
`CONTEXT_FIELD`	This is the name of the field in a message that contains the context value passed to the `ttApplicationContext` procedure as a byte array.
`CREATE_INDEX`	Indicates that an index has been created.
`CREATE_SEQ`	Indicates that a sequence has been created.
`CREATE_SYNONYM`	Indicates that a synonym has been created.
`CREATE_TABLE`	Indicates that a table has been created.
`CREATE_VIEW`	Indicates that a view has been created.
`DELETE`	Indicates that a row has been deleted.
`DROP_COLUMNS`	Indicates that columns have been dropped.
`DROP_INDEX`	Indicates that an index has been dropped.
`DROP_SEQ`	Indicates that a sequence has been dropped.
`DROP_SYNONYM`	Indicates that a synonym has been dropped.
`DROP_TABLE`	Indicates that a table has been dropped.
`DROP_VIEW`	Indicates that a view has been dropped.
`FIRST_FIELD`	This is the name of the field that contains the flag that indicates the first record in a transaction.
`INSERT`	Indicates that a row has been inserted.
`MTYP_FIELD`	This is the name of the field in a message that contains type information.
`MVER_FIELD`	This is the name of the field in a message that contains the transaction log file number of the XLA record.
`NULLS_FIELD`	This is the name of the field in a message that contains the list of fields that have null values.
`REPL_FIELD`	This is the name of the field in a message that contains the flag that indicates that the update was applied by replication.
`TBLNAME_FIELD`	This is the name of the field in a message that contains the table name.
`TBLOWNER_FIELD`	This is the name of the field in a message that specifies the table owner.
`TRUNCATE`	Indicates that a table has been truncated.
`TYPE_FIELD`	This is the name of the field in a message that specifies the message type.
`UPDATE`	Indicates that a row has been updated.
`UPDATE_DESCRIPTOR_FIELD`	This is the name of the field that returns a `ttXlaUpdateDesc_t` structure as a byte array.
`UPDATED_COLUMNS_FIELD`	This is the name of the field in a message that contains the list of updated columns.

XLA Flags

For all update types, the MapMessage instance contains name/value pairs that indicate the following.

Whether this is the first record of a transaction
Whether this is the last record of a transaction
Whether the update was performed by replication
Which table was updated
The owner of the updated table

The name/value pairs that contain these XLA flags are described in Table 6-2. Each name is preceded by two underscores.

Table 6-2 JMS/XLA Flags

Name	Description	Corresponding ttXlaUpdateDesc_t Flag
`__AGING_DELETE`	Indicates that a delete was due to aging. The flag is present only if the XLA update record is due to an aging delete. The `XlaConstants` constant `AGING_DELETE_FIELD` represents this flag.	`TT_AGING`
`__CASCADING_DELETE`	Indicates that a delete was due to a cascading delete. The flag is present only if the XLA update record is due to a cascading delete. The `XlaConstants` constant `CASCADING_DELETE_FIELD` represents this flag.	`TT_CASCDEL`
`__COMMIT`	Indicates that this is the last record in a transaction and that a commit was performed after this operation. This is in the `MapMessage` if `TT_UPDCOMMIT` is on. The `XlaConstants` constant `COMMIT_FIELD` represents this flag.	`TT_UPDCOMMIT`
`__FIRST`	Indicates that this is the first record in a new transaction. This is in the `MapMessage` if `TT_UPDFIRST` is on. The `XlaConstants` constant `FIRST_FIELD` represents this flag.	`TT_UPDFIRST`
`__REPL`	Indicates that this change was applied to the database through replication. This is in the `MapMessage` if `TT_UPDREPL` is on. The `XlaConstants` constant `REPL_FIELD` represents this flag.	`TT_UPDREPL`
`__UPDCOLS`	This is only used for `UPDATETUP` records, indicating that the XLA update descriptor contains a list of columns that were actually modified by the operation. It is specified as a string that contains a semicolon-delimited list of column names and is in the `MapMessage` only if `TT_UPDCOLS` is on. The `XlaConstants` constant `UPDATE_COLUMNS_FIELD` represents this flag.	`TT_UPDCOLS`

Note:

The XlaConstants interface is in the com.timesten.dataserver.jmsxla package.

Applications can use the MapMessage method itemExists() to determine whether a flag is present, and getBoolean() to determine whether a flag is set. As input, specify the XlaConstants constant that corresponds to the flag, such as XlaConstants.AGING_DELETE_FIELD.

Equivalent to using TT_UPDCOMMIT in XLA, you can use the following test in JMS/XLA to see whether this is the last record in a transaction and that a commit was performed after the operation.

if (MapMessage.getBoolean(XlaConstants.COMMIT_FIELD) ) { // Field is set
   ...
}