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E-Maj - Release notes
Bug fixes:
- E-Maj is now installed as a standard extension using the CREATE
- the uninstallation script is renamed emaj_uninstall.sql and includes the
- PostgreSQL versions prior 9.1 are not supported by E-Maj anymore.
- various changes in the functions code to take benefit from the features
brought by 8.4 to 9.1 postgres versions.
- a new emaj_consolidate_rollback_group() function consolidates a rollback
for a group. It means the function transforms a logged rollback already
executed as if it were an unlogged rollback, by deleting all the log
records and marks between the mark used as target for the already
executed logged rollback and the mark that has taged the end of this
- a new emaj_get_consolidable_rollbacks() function returns the list of
logged rollback operations that may be consolidated. Two of the returned
columns can directly feed the emaj_consolidate_rollback_group() function.
It also gives information about the amount of log updates that may be
deleted and the number of marks what would be deleted by a consolidation.
- when postgres version allows it, add event triggers to protect
application or E-Maj components against drop or some table structure
changes. The new functions emaj_disable_protection_by_event_triggers()
and emaj_enable_protection_by_event_triggers() respectively disable and
re-enable these event triggers, if needed.
- in emaj_start_group() and emaj_start_groups() functions, allow to not
supply the mark name parameter. In this case, the default mark name is
built as, using the current timestamp. A mark name set
to NULL or '' is now also transformed into
- in emaj_set_mark_group() and emaj_set_mark_groups() functions, allow to
not supply the mark name parameter. In this case, the default mark name
is built as, using the current timestamp.
- in emaj_stop_group() and emaj_stop_groups() functions, if the supplied
mark name is NULL or '', it is now transformed into
- for emaj_gen_sql_group() and emaj_gen_sql_groups() functions, change the
type of the returned value representing the number of generated sql
statements to BIGINT.
- the purge of the history now keeps the events after the beginning of
possibly in progress rollbacks. It also doesn't purge the internal
emaj_rlbk table anymore.
- in rollback functions, trap all exceptions that may happen when the
rollback uses autonomous transactions with dblink and set the proper
aborted state of the rollback operation in the emaj_rlbk table.
- in error and warning messages, all groups, marks, schemas or tables names
are surrounded by double quotes to improve the readability.
- a new emaj_time_stamp table records the timestamps of main E-Maj events
like groups creation, marks setting and rollbacks, leading to significant
changes in some existing internal tables structure.
- various minor coding enhancements.
- the demonstration script is renamed emaj_demo.sql and enhanced.
- the script supplied to prepare a parallel rollback test environment is
renamed emaj_prepare_parallel_rollback_test.sql and enhanced.
Bug fixes:
- the emaj_gen_sql_group() and emaj_gen_sql_groups() functions now properly
generate an error if the "list of tables/sequences to filter" parameter
is empty.
Bug fixes:
- fix a performance issue with logged rollback operations in some rare
cases, involving tables with primary keys having more than 6 columns.
- fix rollback operation aborts when the E-Maj installation has been
upgraded from 1.1.0 to 1.2.0 and then from 1.2.0 to 1.3.0.
- two new functions, emaj_protect_group() and emaj_unprotect_group(),
respectively set and unset a specific lock on a group. When such a lock
is set on a group, any rollback attempt on this group returns an error.
Protecting a group is only meaningfull and thus possible if it is not an
audit_only group and if it is in logging state. Stopping a protected
group resets the protection.
- two other new functions, emaj_protect_mark_group() and
emaj_unprotect_mark_group(), respectively set and unset a specific lock
on a mark for a group. When such a lock is set on a mark for a group,
any rollback attempt that would jump over the mark returns an error. This
concerns both logged and unlogged rollbacks. Protecting a mark is only
possible if its related group is not an audit_only group and if it is in
logging state. Stopping a group resets the protection set on its marks.
- change the name of log and truncate triggers set by E-Maj on application
tables. The triggers now have the same name for all tables, respectively
emaj_log_trg and emaj_trunc_trg.
- remove the execute rights granted to emaj_viewer role. It is useless,
even for the phppgadmin plugin.
- minor improvements in the code and in comments.
Bug fixes:
- in table emaj_group_def, add a column named grpdef_emaj_names_prefix to
set a specific prefix for all objects created by E-Maj for tables. If
set by the E-Maj administrator, this prefix replaces the default
<schema_name>_<application_table_name>. This removes the existing name
size limit of the tables that E-Maj can handle. All prefixes must be
unique inside an E-Maj installation.
- add 6 columns into the emaj_relation table to record the name of all
E-Maj objects related to each application table or sequence. These
columns are used rather than recomputing E-Maj object names. The
emaj._build_log_seq_name() function is dropped.
- improve locking for start, stop and rollback groups operations. For
start and stop groups operations, decrease the lock level to SHARE ROW
EXCLUSIVE when the postgres version is at least 9.5, to follow the
postgres improvement in setting lock for ALTER TABLE ENABLE/DISABLE
TRIGGER. For rollback operations, increase the lock level up to ACCESS
EXCLUSIVE when log triggers have to be disabled/enabled and when postgres
version is prior 9.5. This decreases the risk of deadlock during rollback
- some minor coding improvements
Bug fixes:
- replace all NOT IN (subquery) by the almost equivalent NOT EXISTS()
syntax. This fixes potential issues with NULL value processing mainly
in the functions that check the E-Maj environment.
- add a CASCADE clause to the DROP FUNCTION statement in the _drop_tbl()
function, to avoid the abort of the emaj_alter_group() function calls
when an application table has been renamed or has been moved into another
- the rollback processing has been largely redesigned and recoded so that
emaj administrators can monitor rollback operations progress. This
feature requires a dblink connection on the same database. Its connection
parameters are configured in a new 'dblink_user_password' entry into the
emaj_param table.
- the rollback processing has also been optimized. The per table rollback
functions are replaced by a more efficient generic table rollback
- for security reason, emaj_viewer roles cannot directly read the
emaj_param table's content any more. Instead, this role may access a new
emaj_visible_param view that provides the same visibility, except for the
value of the new 'dblink_user_password' parameter that is masked.
- the emaj_estimate_rollback_duration() function is replaced by two new
functions, namely emaj_estimate_rollback_group() and
emaj_estimate_rollback_groups(), the later estimating the duration of a
multi-groups rollback. They share some pieces of code with the rollback
functions. A third parameter specifies whether the rollback is logged or
- a new emaj_rollback_activity() function provides information about
in progress rollback operations. It returns a set of rows of type
emaj_rollback_activity_type. They contain a description of each running
rollback operation, as well as a remaining duration estimate and a
percentage of the work already done. emaj_adm and emaj_viewer roles can
call it.
- a new client, emajRollbackMonitor.php, is provided to monitor E-Maj
rollback operations that are currently in progress.
- at create_group() or alter_group() time, a check is added to be sure no
temporary tables and no unlogged tables are recorded into tables groups.
Some other tests on tables groups content have been enforced too.
- the default value of the 'history_retention' parameter is now 1 year
(previously 1 month).
- the emaj_generate_sql() function is renamed emaj_gen_sql_group() for
consistency with other functions names.
- a new emaj_gen_sql_groups() function generates a sql script replaying
all updates recorded for a set of groups between two marks or between a
mark and the current situation.
- both emaj_gen_sql_group() and emaj_gen_sql_groups() functions may have an
additional text array parameter specifying a set of table or sequence
names. This optional parameter represents a filter of tables and/or
sequences to process.
- a new emaj_user_port column is added into each log tables. It holds the
ip port of the remote user who performed the recorded update and
complements the already existing emaj_user_ip column.
- the primary index of each log table is declared as CLUSTER to help the
log tables reorganization.
- various code improvements, in particular taking benefit from the end of
the postgres 8.2 support.
- E-Maj is qualified with postgres 9.3.
- some minor coding improvements such as: the replacement of the mark_state
column in the emaj_mark table by a boolean column named mark_is_deleted ;
the replacement of the group_state column in the emaj_group table by a
boolean column named group_is_logging ; some error message improvements.
Bug fixes:
Bug fixes:
- At the beginning of a rollback operation, if a table known as 'not
needing rollback' at initialisation time is updated before the locking
step, this table will not be rolled back, generating a loss of
consistency between tables of the group. A check is now added, so that
the rollback safely fails if such a case happens.
Bug fixes:
- fix an abort in rollback processing when a deferrable foreign key links
two tables, one not being covered by E-Maj, and the other having events
to rollback.
- to help managing databases having a large number of tables, it is now
possible to spread E-Maj objects on several schemas. E-Maj functions
and technical tables remain on emaj schema (the E-Maj primary schema).
But secondary schemas can hold the log table, sequence and functions
for any application table. All secondary schema names start with 'emaj'.
E-maj administrator can define a secondary schema for any application
table though a new column in emaj_group_def table:
grpdef_log_schema_suffix. E-Maj functions manage the creation and the
deletion of these secondary schemas.
- emaj administrators can define custom tablespaces to be used for log
tables or their indexes on a per table basis. Two new columns in the
emaj_group_def table support this feature: grpdef_log_dat_tsp and
grpdef_log_idx_tsp. If they contain NULL, tspemaj is used if it exists.
- an additional parameter for emaj_stop_group() and emaj_stop_groups()
functions allows to customize the name of the mark set by these functions.
- emaj_verify_all() function now detects more unattended tables and
functions in E-Maj schemas (i.e. not only those which looks like emaj
components). It also detects views, sequences, composite types, domains,
foreign tables, conversions, operators and operator classes that should
not be present in E-Maj schemas. It now only returns one row when no
problem is detected. The function has been optimised to fit performance
needs with databases having a great number of relational objects.
- the sanity checks performed on groups at start_group, set_mark_group and
rollback_group times have been significantly speed up.
- a new emaj_alter_group() function allows to take into account any change
applied in the emaj_group_def table for a given tables group (like
adding to or suppressing from the group tables or sequences, or changing
priority levels or log schema names or tablespaces). It then replaces
the use of emaj_drop_group() followed by emaj_create_group() functions.
- a new emaj_force_stop_group() function can be used to stop a corrupted
tables group, in particular when an application table or a log trigger
has been dropped while the tables group was in LOGGING state.
- at tables group creation time, issue a warning when a sequence is linked
to a serial column whose table is not protected by E-Maj or do not belong
to the same tables group as the sequence.
- a new variation of the emaj_get_previous_mark_group() function returns
the name of the mark that immediately precedes a given mark for a group.
- the emaj_delete_before_mark_group() now tries to purge the emaj_hist
table, similarly to what start_group functions do. This simplifies the
management of the emaj_hist table when groups are never stopped and
- emaj_log_stat_group() now returns a result (with all rows numbers set to
0) instead of an error when the supplied start mark is NULL and no mark
are yet recorded for the examined group.
- during rollback operations, use a less constraining EXCLUSIVE locking
mode on the application tables to process, allowing other transactions
to concurrently access these tables with SELECT statements.
- in rollback functions, add ONLY clause to UPDATE and DELETE statement so
that the rollback operations of mother tables are safer and more
efficient when table inheritance is used.
- when setting a mark on one or several tables groups, record the state of
all sequences as early as possible (before processing tables) ; as no
lock can be set on a sequence, this decreases the risk of another
concurrently running transaction modifying one of these sequences.
- process more safely the EMAJ_LAST_MARK keyword when system time changes,
the mark search not being based on timestamp any more.
- minor improvements in the code and in comments.
Bug fixes:
- let emaj_force_drop_group() works when an application schema or relation
has been previously dropped.
- allow an emaj_adm role to effectively execute the emaj_reset_group()
function without error on TRUNCATE statements when the group has been
created by someone else.
- really rollback sequences in the desired priority order.
- in emaj_reset_group() function, fix a very rare case where some rows
from the internal emaj_sequence table could be abusively deleted (in
case an application sequence would be named as an emaj log sequence!).
- fix a bug in emaj_rename_mark_group() function: when a unique mark has
been set for several tables groups, renaming this mark for one of these
groups led to a corrupted emaj_sequence table for rows concerning the
same mark and the other groups.
- properly set to 0 the mark_log_rows_before_next column of the internal
emaj_mark table for the marks set at emaj_stop_group time.
- largely improve the processing of foreing keys during rollback operations:
foreign keys are only dropped and recreated when this is really needed
and the rollback functions take benefit of foreign keys declared as
DEFERRABLE. The emaj_estimate_rollback_duration() function is adjusted
accordingly, using a new optional parameter, avg_fkey_check_duration,
used when no statistics from previous rollbacks is available.
- tspemaj tablespace is now optional. If it exists at emaj installation
time, technical tables are stored on it. If it exists at
emaj_create_group() time, log tables and index are stored on it. If
tspemaj doesn't exist, default_tablespace is used.
- improve the error message returned by emaj_rename_mark_group() if the
supplied new mark name is NULL.
- minor internal improvements in rollback functions, and in
emaj_delete_mark_group() and emaj_delete_before_mark_group() functions.
Bug fixes:
- fix an incorrect state for marks generated at stop_group(s) time. Being
previously left as ACTIVE after the emaj_stop_group() or
emaj_stop_groups() functions calls, a rollback to this mark after a
restart of the group led to sequence values corruption.
- indexes of technical emaj tables are now also located on tspemaj
tablespace (if exists)
- fix a SQL injection hole in 2 functions by testing more carefuly supplied
- add an optional "resetLog" boolean parameter to the emaj_start_group()
and emaj_start_groups() functions, indicating if the old log records must
be physicaly deleted or not. By default, or when this third parameter is
set to true, old log records of a group are deleted (i.e. the group is
reset) at start group time. If the group is not reset at start time, all
old related marks and log tables rows cannot be used for any rollback
operation any more. Nevertheless, log rows remain visible, old marks can
be deleted, renamed or commented, and log statistics can be requested.
- now that logs may survive to a group start, a mark is automaticaly set
at group stop time so that this operation is clearly visible in the marks
list; This mark is named STOP_xxx where this suffix represents the time
of the day.
- the emaj_rollback_and_stop_group() and emaj_rollback_and_stop_groups()
functions are suppressed. They were not really useful and they left
inconsistent data in log tables, which may lead to trouble now that
it is possible to start a tables group without deleting old log rows and
- add a new emaj_generate_sql function that generates a sql script
corresponding to all updates performed on a tables group between two
marks or between a mark and the current situation, and stores it into a
given file (only available in postgres 8.3+).
- in emaj_snap_group() and emaj_snap_log_group() functions, improve the
format of the _INFO file: the timestamp is now reported with the date and
time format of the client.
- in emaj_snap_group() and emaj_snap_log_group() functions, add an input
parameter to specify the options to used in COPY TO statements, like CSV,
- in emaj_snap_group() function, improve the format of the sequences files:
remove the useless log_cnt column and use the same columns list for all
postgres versions.
- in emaj_snap_log_group() function, allow a NULL or empty string as last
mark, indicating the current state. In such a case, the file containing
sequences characteristics at current state is named using the current
- a TRUNCATE sql verb is now allowed on audit_only tables group even in
logging state. The execution of a truncate statement on a table is
recorded in the associated log table, the emaj_verb column being set to
- add a column into the emaj_mark table to maintain statistics about the
total number of log rows recorded between the mark and the following one.
This is useful to speedup the retrieval of this data, for instance by the
phpPgAdmin plugin.
- rework the internal emaj sequences mechanism. Using a unique global
sequence. It is now possible to sort log rows for all tables by their
creation order, so that emaj_generate_sql() function result remains safe
even in case of system time change. The sequence associated to each log
table remains to speed up the statistics delivery but its increment is now
1. In log tables, the emaj_id column is renamed emaj_gid.
- in groups creation, start or rollback functions, improve the detection of
foreign keys referencing tables outside the groups or tables referenced
by foreign keys from tables outside the groups: tables from audit_only
groups are now ignored because the potential problem detected with
foreign keys only concerns rollback operations.
- minor improvement in messages produced by emaj.emaj_verify_all() function.
- minor improvements in the code and in comments.
Bug fixes:
- fix a bad error message in emaj_create_group() function when the group
to create is not referenced in emaj_group_def table.
- fix rollback function generation for cases when a table name includes
backslash characters.
- fix emaj_snap_group for cases when any column from the pkey contains at
least one special character that obliged to quote the column name in
- in emaj_snap_group() and emaj_snap_log_group() functions, verify that the
supplied directory parameter is not null.
- avoid potential problem with the generated rollback functions, by
explicitely fixing the columns list in the INSERT statement that reverts
recorded DELETE events.
- enhance emaj_snap_group() function so that it can be used by emaj_adm
granted role. The use of the function is also recorded into the emaj_hist
table. The files are now created in CSV format.
- create a new emaj_snap_log_group() function to snap all log tables
related to a group into a supplied directory. Only rows corresponding
to a mark interval are snapped. One CSV file is created for each table.
Sequences state at starting mark and ending mark are also stored into
2 specific files.
- the emaj_verify_all() function also performs various checks on all tables
groups to verify their consistency and ability to be safely managed by
E-Maj functions.
- add a primary key (and its associated index) to log tables to speed up
the rollback operations or detailed statistics requests on large log
Bug fixes:
- fix emaj_delete_mark_group() and emaj_delete_before_mark_group()
operations. When a mark set for several groups by an
emaj_set_mark_groups() function, is deleted for a single group, it was
not usable any more (in particular for rollback) for the other groups
for which the mark remained active.
- fix errors when using schema, column, sequence or mark names including
unusual characters like apostrophs or commas.
- fix a possible "division by zero" error in
emaj_estimate_rollback_duration() function.
- fix a bug in emaj_snap_group() function in building the list of the
columns belonging to the table's pkey, after one of these columns has
been renamed.
- on PostgreSQL 9.1 and later, E-Maj can be installed with a SQL "CREATE
EXTENSION" statement. If this version is already installed using the
usual script, it can also be transformed into EXTENSION.
- create a new type of rollback: logged rollback, i.e. rollback executed
without disabling the log triggers. As a result, the application table
updates performed by the logged rollback are also recorded in emaj log
tables, and a logged rollback can be ... rollbacked too! Two marks are
automatically set to represent both before and after rollback states of
the table group.
- a new emaj_delete_before_mark_group() function deletes all marks prior
(and not including) a given mark. With this functions, it is easy to let
groups in LOGGING state during a long period, without being limited by
the disk space for log tables. The drawback is the time needed to
delete large amount of logs, as log tables cannot be TRUNCATEd.
- a new emaj_get_previous_mark_group() function returns the name of the
mark that immediately precedes a given date and time for a group. This
may help in using the emaj_delete_before_mark_group() function.
- emaj_delete_mark_group() function now returns 1 (i.e. the number of
deleted mark), to be consistent with the data returned by the new
emaj_delete_before_mark_group() function.
- the E-Maj administrator can set priority order between tables when he
describes a group content in emaj_grpdef table. This lets the emaj
administrator manage a processing order that minimize deadlock risks.
A new column, named grpdef_priority, and that can be left to NULL,
handles this concept. In emaj operations and in particular when locks
are set on tables, tables are processed in ascending order of priority,
NULLs being processed last, and in alphabetic order for schema name +
table name for tables described with same priority level.
- a new set of functions give the E-Maj administrator to start, stop,
set marks or rollback on a set of groups in a single operation and
transaction. emaj_start_groups, emaj_stop_groups, emaj_set_mark_groups,
emaj_rollback_groups, emaj_logged_rollback_groups and
emaj_rollback_and_stop_groups take as first argument an array of group
- emaj_param rows describing parameters default values are no longer
inserted at installation time. The default values are only set when
needed in functions. To change the default values, E-Maj administrator
needs to insert rows into emaj_param (instead of update them).
- a new emaj_comment_group function sets (or resets) a comment on an
existing group.
- a new emaj_comment_mark_group function sets (or resets) a comment on an
existing mark.
- the general log_only parameter is replaced by a parameter set at group
level. A new optional boolean parameter is added to the
emaj_create_group() function, indicating whether the new group supports
rollback operations or not. By creating 'audit_only' groups (i.e. "non
rollbackable"), it is possible to activate log on tables that do not have
any primary key.
- in each log table created by emaj_create_group() function, add an
emaj_inet_addr column, as a complement to the emaj_user column, to
register the ip address of the user who has generated the table update.
- in emaj_log_stat_group() and emaj_detailed_log_stat_group(), empty
strings can be supplied as mark names. In such a case, there are
processed as NULL values.
- allow use of searching or deleting marks for groups in IDLE state.
- in parallel rollback processing, "subgroups" are now named "sessions"
to avoid confusion in multi-groups rollbacks.
- in emaj_estimate_rollback_duration(), check that the group is in LOGGING
- in emaj_create_group(), explicitely check that no table or sequence
already belong to another created group.
- in emaj_hist table, add a column containing the id of the insertion
- a comment has been added to all E-Maj tables, types and roles, as well
as to all functions callable by users.
- a check is performed at the beginning of the E-Maj installation to be
sure that the current postgres version is compatible with E-Maj, the user
performing the installation is a superuser and tspemaj tablespace exists.
- a check on the max_prepared_transaction is performed at installation
time and a warning is reported if the setting would block the use of the
parallel rollback feature.
- add a check at group creation, set mark and rollback times to verify that
the group has been created with a compatible postgres version (for
instance, a group created in 8.3 should not be directly used in 8.4).
Bug fixes:
- in emaj_create_group(), check the supplied group name is not null, and
not empty.
- during emaj_start_group() avoid double lock of tables and reoder events
in the emaj_hist table.
- in emaj_verify_all() function, add a check on orphan truncate functions.
- a missing check has been added in internal _verify_group() function.
- to avoid potential data corruption at rollback time if the system date
and time changes during E-Maj activity period, use serial id instead of
timestamp for emaj_mark, emaj_sequence and emaj_seq_hole tables content
- change the primary key columns identification. Starting from pg 9.0,
column names must be read from pg_attribute with the table's definition,
using pg_index.indkey, as the column names with the index definition is
not safe any more in case of column renaming.
- emaj_snap_group(): avoid setting explicit locks on tables because it is
not necessary to get a coherent image of all tables of the group.
- the emaj_log_stat_group() function has been refactored. A new internal
_log_stat_table() function has been created.
- the group_creation_datetime column of the emaj_group table is now
initialized with the transaction timestamp instead of the clock timestamp.
- main functions set a lock on the emaj_group row representing the working
group to prevent simultaneous execution of these functions.
- in emaj_start_group() and emaj_set_mark_group() functions, a mark name may
contain '%' wild characters. They are automatically replaced by a sequence
of digits from the current time.
- while locking tables of a group, if a deadlock occurs, the locking
operation is cancelled and retried up to 5 times before the transaction
aborts. The comment in the history table reports the number of locked
tables and the number of deadlocks encountered.
Bug fixes:
- fix a case of infinite wait on parallel rollback at foreign key processing
when several tables affected to different sub-groups have a foreign key
referencing a table that has no row to rollback.
- in emaj_start_group() and emaj_set_mark_group() functions, avoid empty or
NULL mark names. If the supplied mark name is NULL or empty, a name is
automaticaly generated as "MARK_" followed by digits from the current time.
- fix an invalid column name referenced in emaj_delete_mark_group() function.
- in emaj_delete_mark_group() function, fix an erroneous information
inserted into the emaj_hist table.
- during emaj_drop_group() operation, delete now all rows related to the
tables belonging to the dropped group from emaj_sequence and emaj_seq_hole
- fix a bug in the E-Maj history table purge. If a group is in logging state
for a longer period than the history retention delay ('history_retention'
parameter), the oldest events in the history were unintentionly purged.
- set appropriate grants to internal functions _forbid_truncate_fnct().
- fix the postgres version detection for alpha or beta releases version
- fix a minor bug in reporting list of existing triggers on application
table at emaj_create_group time.
- use a more robust lack of primary key detection.
- a new emaj_estimate_rollback_duration() function computes an approximate
value for the duration of a rollback operation. It uses statistics
recorded in the new emaj_rlbk_stat table, as well as 4 new parameters.
- the emaj_set_mark_group function now returns the number of processed
tables and sequences as other main emaj functions.
- add a check in emaj_log_stat_group and emaj_detailed_log_stat_group
functions if the supplied first mark is greater than the last_mark.
- in emaj_detailed_log_stat_group function, change the INS/UPD/DEL values
returned for emaj_verb column into more explicit terms (INSERT/UPDATE/
- emaj_detailed_log_stat_group, emaj_delete_mark and emaj_rename_mark
functions now accept EMAJ_LAST_MARK keyword as existing mark names.
- add a check at mark creation times to forbide EMAJ_LAST_MARK name.
- split column hist_type from emaj_hist table into 2 columns: hist_function
and hist_event
- during rollback operations, move the rollback of application sequences at
the very end of the operation, as these rollback (ALTER SEQUENCE) are not
transaction safe.
- log sequences are now reset at emaj_reset_group or emaj_start_group time.
This should avoid potential long term issue if the log sequence reaches
the upper limit of serial id.
- starting from postgres version 8.4, a trigger is created on all tables
belonging to a group in order to forbid TRUNCATE SQL verb during E-Maj
logging time. These triggers are named <schema>_<table>_emaj_trunc_trg.
They all call a new emaj._forbid_truncate_fnct() function. The log trigger
names change also, becoming <schema>_<table>_emaj_log_trg.
Bug Fixes:
- in rollback_and_stop_group function, an error was abnormaly returned when
not all tables of the group needed to be effectively rollbacked.
- 2 error messages in emaj_start_group() didn't include the right function
- during rollback operations, do not rollback the sequences associated to
the log tables any more. Before, if a problem occurred during a rollback
operation, the sequences of already rollbacked tables were left in an
inconsistent state.
- fix grant issues for emaj_adm role.
- enlarge the usage of the emaj_delete_mark_group function. It is now
possible to delete the first mark of a group. As a result, all rows from
log tables that become useless are deleted. This permits to reclaim disk
space in tspemaj tablespace if needed. At least one mark must remain
active. But a mark cannot be deleted if the group is not in LOGGING state.
- a call to emaj_stop_group function for a group that is already in IDLE
state now only produces a warning instead of an error (exception).
- minor coding improvement in emajParallelRollback.php module (better checks
of supplied group and mark names).
- add a column in emaj_group to record the creation date and time of groups.
- decrease the level of locks set at emaj_set_mark_group time from EXCLUSIVE
to ROW EXCLUSIVE so that locks generated by vacuum don't conflict with
emaj activity.
- add an explicit ACCESS EXCLUSIVE lock at emaj_stop_group time to decrease
the risk of deadlock.
- rename all internal functions by removing the 'emaj' prefix. So all emaj_
functions are now the only functions callable by users.
- add identifier of the updating transactions (txid) in log tables and the
txid of the emaj_set_mark_group command in the emaj_mark table. This is
for information purpose until now.
- add a emaj_force_drop_group function to drop groups that cannot be dropped
with the standart emaj_drop_group function, because of any unconsistency
of these group. Create an internal _drop_group function to factorize the
common parts of both emaj_drop_group and emaj_force_drop_group functions.
- add 2 roles without logging capacity:
- emaj_viewer can look at the log and emaj tables' content (application
support role can be granted this role),
- emaj_adm can execute all (but emaj_snap_group) functions without being
superuser (an "emaj administrator" can be granted this role).
- add a emaj_rename_mark_group function to rename an existing mark.
- an uninstall.sql script is provided to ... uninstall E-Maj components from
a database.
- a minor change to execute E-Maj with PostgreSQL 9.0.
- in emaj_create_group function, improve the check that tables have no
triggers that could be a problem at rollback time.
- the name of deleted marks due to a rollback operation is recorded in the
history table.
- marks that are deleted either by an emaj_rollback_group function call or
by an emaj_delete_mark_group function call are now physicaly deleted.
- the primary key of emaj_mark table becomes (group-name, mark-name) instead
of the mark-timestamp.
- E-Maj can be used with postgres 9.0.
- rename emaj_log_stat_group into emaj_detailed_log_stat_group. The
associated emaj_log_stat_type type is renamed into
- The emaj_rlbk_stat_group is renamed into emaj_log_stat_group. An
additional end_mark parameter allows to ask for statistics on a period of
time between two marks.The associated emaj_rlbk_stat_type type is renamed
into emaj_log_stat_type.
Bug fixes:
- in rollback, solve problem with a loss of mark for other groups than the
rollbacked one.
- in emaj_reset_group, the sequences related to log tables were not deleted
when application table name contained uppercase characters
- add a emaj_snap_group function for test purpose that snaps all tables
and sequences of a group on individual files located into a given
- add a warning at create_group time if tables have (non emaj) triggers.
- decrease the level of locks set at emaj_create_group or
emaj_set_mark_group time from ACCESS EXCLUSIVE (the default lock mode)
to EXCLUSIVE so that ACCESS SHARE locks generated by read accesses don't
conflict with emaj activity.
- minor coding improvement.
- this version is also tested with postgresql 9.0 beta 2.
Bug fixes:
- in log_only mode, solve the problem encountered when creating log for
a table without primary key.
- fix the error occuring when a emaj_reset_group was not executed prior an
emaj_drop_group. Take the opportunity to use cascading deletes provided by
foreign keys referencing emaj_group table.
- fix the emaj_create_group function to get correct numbers of tables and
sequences in emaj_group table.
- fix rollback aborts on UPDATEs when several clients accessed the
database in parallel resulting in both log rows for each UPDATE (one for
old values and the other for new values) not strictly in sequence.
- when rollbacking a table, finaly also rollback the state of the sequence
associated to the log id so that the statistics produced by the
function emaj_rlbk_stat_group are correct after a rollback operation.
- fix error when rollbacking tables having foreign keys with case sensitive
- add a feature to perform parallel rollbacks, in order to speed up the
rollback operations on multi-processor servers. A PHP command is created
for this purpose: emajParallelRollback.php.
- the emaj_reset_group function is not necessary any more before starting
a group; the log purge is automaticaly done at emaj_start_group function;
But the emaj_reset_function remains so user can purge log tables sooner.
- issue a warning at emaj_create_group, emaj_start_group and
emaj_rollback_group if either a table of the group has a foreign key that
reference a table outside the group or a table of the group is referenced
by a table outside the group.
- before a rollback operation, drop the foreign keys belonging to or
referencing any group's table and recreate them after
- add a serial id to the emaj_hist table to avoid potential duplicate key
conditions if 2 events happen in the same micro-second.
- the table previsously named emaj_group becomes emaj_group_def, column
names being slightly changed. This impact ts E-maj usage.
- a new table emaj_relation, records working data about the relation
belonging to all created groups. It provides a stability of the group
composition during its entire life (between emaj_create_group and
emaj_drop_group function calls).
- a new internal table emaj_group maintain the state of managed groups.
- a new table emaj_param stores E-maj parameters. A first emaj_version
parameter records the current emaj version.
- the emaj_delete_group function has been renamed into emaj_drop_group.
This impacts E-maj usage.
- add a parameter named 'log_only' that allow to configure E-maj in a mode
that disables rollback operations. This permits users to test E-maj
logging with tables for which a primary key is not yet created.
- add an automatic deletion of oldest rows in the emaj_hist table. To
achieve this, a parameter, named 'history_retention' is created in the
emaj_param table, with a default value of 1 month. This value can be
changed by the user. This history purge is done at every emaj_start_group
- enhance the checks of emaj environment, by checking the internal
consistency at group level.
- provide to users a function that checks that no residual functions or log
tables remain in the emaj environment.
- in all rollback functions (in parallel or not) it is possible for user to
use the keyword 'EMAJ_LAST_MARK' as mark name. This pseudo name is
equivalent to the last active mark that exists for the group. It can also
be used in emaj_rlbk_stat_group function
Bug fixes:
- change emaj_delete_group, emaj_start_group and emaj_reset_group functions
to add a check that the group to process is not in logging state
- add an emaj_rollback_and_stop_group function to rollback a table_group and
stop it at the same time.
This allow to not delete the rollbacked rows from log tables and then
speed up the rollback function when there is no need to keep any previous
mark active.
- when an emaj_stop_group function is performed, the marks in emaj.marks
table are not physicaly deleted but their state just becomes "deleted".
The associated data in emaj_sequence table (that record the serial value
of each log table) are also not deleted.
This allow to find marks timestamps if log tables are used for application
debugging purpose.
The emaj_reset_group function physicaly deletes the marks for the group at
the same time it truncates the related log tables.
Note that deleted marks can be referenced in emaj_log_stat_group function
- change column names from emaj_hist table to get a better consistency
between table name and columns name prefix
Bug fixes:
- in rollback operations, don't delete the mark used to rollback to, and its
associated data for sequences, because it can be useful for a future use
if the application continues after the rollback operation.
Bug fixes:
- the UPDATE statements generated for the rollback functions did not handle
properly the columns list of the SET clause.
- supply the right test-emaj.sql file !
Bug fixes:
- when a table has several indexes, the UPDATE or DELETE statements
generated by the emaj_rollback_group function was often erroneous.
- replace the current_timestamp default value for emaj_changed column of log
tables by clock_timestamp() so that every log row has its own creation
First released version