NAME
odb - object-relational mapping (ORM) compiler for C++
SYNOPSIS
odb [options] file [file...]
DESCRIPTION
Given a set of C++ classes in a header file, odb
generates C++ code that allows you to persist, query, and update objects
of these classes in a relational database (RDBMS). The relational
database that the generated code should target is specified with the
required --database
option (see below).
For an input file in the form name.hxx
(other
file extensions can be used instead of .hxx
),
in the single-database mode (the default), the generated C++ files
by default have the following names:
name-odb.hxx
(header file),
name-odb.ixx
(inline file), and
name-odb.cxx
(source file).
Additionally, if the --generate-schema
option is
specified and the sql
schema format is requested (see
--schema-format
), the name.sql
database schema file is generated. If the separate
schema format is requested, the database creation code is generated
into the separate name-schema.cxx
file.
In the multi-database mode (see the --multi-database
option below), the generated files corresponding to the
common
database have the same names as in the
single-database mode. For other databases, the file names include
the database name:
name-odb-db.hxx
,
name-odb-db.ixx
,
name-odb-db.cxx
,
name-db.sql
, and
name-schema-db.cxx
(where db
is the database name).
OPTIONS
--help
- Print usage information and exit.
--version
- Print version and exit.
-I
dir
- Add dir to the beginning of the list of directories to be searched
for included header files.
-D
name[=def]
- Define macro name with definition def. If definition is
omitted, define name to be 1.
-U
name
- Cancel any previous definitions of macro name, either built-in or
provided with the
-D
option.
--database
|-d
db
- Generate code for the db database. Valid values are
mssql
, mysql
,
oracle
, pgsql
,
sqlite
, and common
(multi-database
mode only).
--multi-database
|-m
type
- Enable multi-database support and specify its type. Valid values for this
option are
static
and dynamic
.
In the multi-database mode, options that determine the kind (for example,
--schema-format
), names (for example,
--odb-file-suffix
), or content (for example, prologue
and epilogue options) of the output files can be prefixed with the database
name followed by a colon, for example, mysql:value
. This
restricts the value of such an option to only apply to generated files
corresponding to this database.
--default-database
db
- When static multi-database support is used, specify the database that should
be made the default. When dynamic multi-database support is used,
common
is always made the default database.
--generate-query
|-q
- Generate query support code. Without this support you cannot use views and
can only load objects via their ids.
--generate-prepared
- Generate prepared query execution support code.
--omit-unprepared
- Omit un-prepared (once-off) query execution support code.
--generate-session
|-e
- Generate session support code. With this option session support will be
enabled by default for all the persistent classes except those for which it
was explicitly disabled using the
db session
pragma.
--generate-schema
|-s
- Generate the database schema. The database schema contains SQL statements
that create database tables necessary to store persistent classes defined in
the file being compiled. Note that by applying this schema, all the existing
information stored in such tables will be lost.
Depending on the database being used (--database
option), the schema is generated either as a standalone SQL file or embedded
into the generated C++ code. By default the SQL file is generated for the
MySQL, PostgreSQL, Oracle, and Microsoft SQL Server databases and the schema
is embedded into the C++ code for the SQLite database. Use the
--schema-format
option to alter the default schema
format.
If database schema evolution support is enabled (that is, the object
model version is specified), then this option also triggers the generation
of database schema migration statements, again either as standalong SQL
files or embedded into the generated C++ code. You can suppress the
generation of schema migration statements by specifying the
--suppress-migration
option.
--generate-schema-only
- Generate only the database schema. Note that this option is only valid when
generating schema as a standalone SQL file (see
--schema-format
for details).
--suppress-migration
- Suppress the generation of database schema migration statements.
--suppress-schema-version
- Suppress the generation of schema version table. If you specify this option
then you are also expected to manually specify the database schema version
and migration state at runtime using the
odb::database::schema_version()
function.
--schema-version-table
name
- Specify the alternative schema version table name instead of the default
schema_version
. If you specify this option then you are
also expected to manually specify the schema version table name at runtime
using the odb::database::schema_version_table()
function. The table name can be qualified.
--schema-format
format
- Generate the database schema in the specified format. Pass
sql
as format to generate the database schema as
a standalone SQL file or pass embedded
to embed the
schema into the generated C++ code. The separate
value
is similar to embedded
except the schema creation code
is generated into a separate C++ file (name-schema.cxx
by default). This value is primarily useful if you want to place the schema
creation functionality into a separate program or library. Repeat this
option to generate the same database schema in multiple formats.
--omit-drop
- Omit
DROP
statements from the generated database schema.
--omit-create
- Omit
CREATE
statements from the generated database
schema.
--schema-name
name
- Use name as the database schema name. Schema names are primarily used
to distinguish between multiple embedded schemas in the schema catalog. They
are not to be confused with database schemas (database namespaces) which are
specified with the
--schema
option. If this option is
not specified, the empty name, which is the default schema name, is used.
--fkeys-deferrable-mode
m
- Use constraint checking mode m in foreign keys generated for object
relationships. Valid values for this option are
not_deferrable
, immediate
, and
deferred
(default). MySQL and SQL Server do not support
deferrable foreign keys and for these databases such keys are generated
commented out. Other foreign keys generated by the ODB compiler (such as the
ones used to support containers and polymorphic hierarchies) are always
generated as not deferrable.
Note also that if you use either not_deferrable
or
immediate
mode, then the order in which you persist,
update, and erase objects within a transaction becomes important.
--default-pointer
ptr
- Use ptr as the default pointer for persistent objects and views.
Objects and views that do not have a pointer assigned with the
db
pointer
pragma will use this pointer by default. The value of
this option can be *
which denotes the raw pointer and
is the default, or qualified name of a smart pointer class template, for
example, std::auto_ptr
. In the latter case, the ODB
compiler constructs the object or view pointer by adding a single template
argument of the object or view type to the qualified name, for example
std::auto_ptr<object>
. The ODB runtime uses object
and view pointers to return, and, in case of objects, pass and cache
dynamically allocated instances of object and view types.
Except for the raw pointer and the standard smart pointers defined in the
<memory>
header file, you are expected to include the
definition of the default pointer at the beginning of the generated header
file. There are two common ways to achieve this: you can either include the
necessary header in the file being compiled or you can use the
--hxx-prologue
option to add the necessary
#include
directive to the generated code.
--session-type
type
- Use type as the alternative session type instead of the default
odb::session
. This option can be used to specify a
custom session implementation to be use by the persistent classes. Note that
you will also need to include the definition of the custom session type into
the generated header file. This is normally achieved with the
--hxx-prologue*
options.
--profile
|-p
name
- Specify a profile that should be used during compilation. A profile is an
options file. The ODB compiler first looks for a database-specific version
with the name constructed by appending the
-
database
.options
suffix to name, where database
is the database
name as specified with the --database
option. If this
file is not found, then the ODB compiler looks for a database-independant
version with the name constructed by appending just the
.options
suffix.
The profile options files are searched for in the same set of directories
as C++ headers included with the #include <...>
directive (built-in paths plus those specified with the
-I
options). The options file is first searched for in
the directory itself and then in its odb/
subdirectory.
For the format of the options file refer to the
--options-file
option below. You can repeat this option
to specify more than one profile.
--at-once
- Generate code for all the input files as well as for all the files that they
include at once. The result is a single set of source/schema files that
contain all the generated code. If more than one input file is specified
together with this option, then the
--input-name
option
must also be specified in order to provide the base name for the output
files. In this case, the directory part of such a base name is used as the
location of the combined file. This can be important for the
#include
directive resolution.
--schema
schema
- Specify a database schema (database namespace) that should be assigned to
the persistent classes in the file being compiled. Database schemas are not
to be confused with database schema names (schema catalog names) which are
specified with the
--schema-name
option.
--export-symbol
symbol
- Insert symbol in places where DLL export/import control statements
(
__declspec(dllexport/dllimport)
) are necessary. See
also the --extern-symbol
option below.
--extern-symbol
symbol
- If symbol is defined, insert it in places where a template
instantiation must be declared
extern
. This option is
normally used together with --export-symbol
when both
multi-database support and queries are enabled.
--std
version
- Specify the C++ standard that should be used during compilation. Valid
values are
c++98
(default), c++11
,
and c++14
.
--warn-hard-add
- Warn about hard-added data members.
--warn-hard-delete
- Warn about hard-deleted data members and persistent classes.
--warn-hard
- Warn about both hard-added and hard-deleted data members and persistent
classes.
--output-dir
|-o
dir
- Write the generated files to dir instead of the current directory.
--input-name
name
- Use name instead of the input file to derive the names of the
generated files. If the
--at-once
option is specified,
then the directory part of name is used as the location of the
combined file. Refer to the --at-once
option for
details.
--changelog
file
- Read/write changelog from/to file instead of the default changelog
file. The default changelog file name is derived from the input file name
and it is placed into the same directory as the input file. Note that the
--output-dir
option does not affect the changelog file
location. In other words, by default, the changelog file is treated as
another input rather than output even though the ODB compiler may modify it.
Use the --changelog-in
and
--changelog-out
options to specify different input and
output chaneglog files.
--changelog-in
file
- Read changelog from file instead of the default changelog file. If
this option is specified, then you must also specify the output chanegelog
file with
--changelog-out
.
--changelog-out
file
- Write changelog to file instead of the default changelog file. If
this option is specified, then you must also specify the input chanegelog
file with
--changelog-in
.
--changelog-dir
dir
- Use dir instead of the input file directory as the changelog file
directory. This directory is also added to changelog files specified with
the
--changelog
, --changelog-in
, and
--changelog-in
options unless they are absolute paths.
--init-changelog
- Force re-initialization of the changelog even if one exists (all the
existing change history will be lost). This option is primarily useful for
automated testing.
--odb-file-suffix
suffix
- Use suffix to construct the names of the generated C++ files. In the
single-database mode the default value for this option is
-odb
. In the multi-database mode it is
-odb
for the files corresponding to the
common
database and -odb-db
(where db
is the database name) for other databases.
--sql-file-suffix
suffix
- Use suffix to construct the name of the generated schema SQL file. In
the single-database mode by default no suffix is used. In the multi-database
mode the default value for this option is
-db
(where db
is the database name).
--schema-file-suffix
suffix
- Use suffix to construct the name of the generated schema C++ source
file. In the single-database mode the default value for this option is
-schema
. In the multi-database mode it is
-schema-db
(where db
is the
database name). See the --schema-format
option for
details.
--changelog-file-suffix
sfx
- Use sfx to construct the name of the changelog file. In the
single-database mode by default no suffix is used. In the multi-database
mode the default value for this option is
-db
(where db
is the database name).
--hxx-suffix
suffix
- Use suffix instead of the default
.hxx
to
construct the name of the generated C++ header file.
--ixx-suffix
suffix
- Use suffix instead of the default
.ixx
to
construct the name of the generated C++ inline file.
--cxx-suffix
suffix
- Use suffix instead of the default
.cxx
to
construct the name of the generated C++ source file.
--sql-suffix
suffix
- Use suffix instead of the default
.sql
to
construct the name of the generated database schema file.
--changelog-suffix
suffix
- Use suffix instead of the default
.xml
to
construct the name of the changelog file.
--hxx-prologue
text
- Insert text at the beginning of the generated C++ header file.
--ixx-prologue
text
- Insert text at the beginning of the generated C++ inline file.
--cxx-prologue
text
- Insert text at the beginning of the generated C++ source file.
--schema-prologue
text
- Insert text at the beginning of the generated schema C++ source file.
--sql-prologue
text
- Insert text at the beginning of the generated database schema file.
--migration-prologue
text
- Insert text at the beginning of the generated database migration
file.
--sql-interlude
text
- Insert text after all the
DROP
and before any
CREATE
statements in the generated database schema file.
--hxx-epilogue
text
- Insert text at the end of the generated C++ header file.
--ixx-epilogue
text
- Insert text at the end of the generated C++ inline file.
--cxx-epilogue
text
- Insert text at the end of the generated C++ source file.
--schema-epilogue
text
- Insert text at the end of the generated schema C++ source file.
--sql-epilogue
text
- Insert text at the end of the generated database schema file.
--migration-epilogue
text
- Insert text at the end of the generated database migration file.
--hxx-prologue-file
file
- Insert the content of file at the beginning of the generated C++
header file.
--ixx-prologue-file
file
- Insert the content of file at the beginning of the generated C++
inline file.
--cxx-prologue-file
file
- Insert the content of file at the beginning of the generated C++
source file.
--schema-prologue-file
file
- Insert the content of file at the beginning of the generated schema
C++ source file.
--sql-prologue-file
file
- Insert the content of file at the beginning of the generated database
schema file.
--migration-prologue-file
f
- Insert the content of file f at the beginning of the generated
database migration file.
--sql-interlude-file
file
- Insert the content of file after all the
DROP
and
before any CREATE
statements in the generated database
schema file.
--hxx-epilogue-file
file
- Insert the content of file at the end of the generated C++ header
file.
--ixx-epilogue-file
file
- Insert the content of file at the end of the generated C++ inline
file.
--cxx-epilogue-file
file
- Insert the content of file at the end of the generated C++ source
file.
--schema-epilogue-file
file
- Insert the content of file at the end of the generated schema C++
source file.
--sql-epilogue-file
file
- Insert the content of file at the end of the generated database
schema file.
--migration-epilogue-file
f
- Insert the content of file f at the end of the generated database
migration file.
--odb-prologue
text
- Compile text before the input header file. This option allows you to
add additional declarations, such as custom traits specializations, to the
ODB compilation process.
--odb-prologue-file
file
- Compile file contents before the input header file. Prologue files
are compiled after all the prologue text fragments
(
--odb-prologue
option).
--odb-epilogue
text
- Compile text after the input header file. This option allows you to
add additional declarations, such as custom traits specializations, to the
ODB compilation process.
--odb-epilogue-file
file
- Compile file contents after the input header file. Epilogue files are
compiled after all the epilogue text fragments
(
--odb-epilogue
option).
--table-prefix
prefix
- Add prefix to table names and, for databases that have global index
and/or foreign key names, to those names as well. The prefix is added to
both names that were specified with the
db table
and
db index
pragmas and those that were automatically
derived from class and data member names. If you require a separator, such
as an underscore, between the prefix and the name, then you should include
it into the prefix value.
--index-suffix
suffix
- Use suffix instead of the default
_i
to construct
index names. The suffix is only added to names that were automatically
derived from data member names. If you require a separator, such as an
underscore, between the name and the suffix, then you should include it into
the suffix value.
--fkey-suffix
suffix
- Use suffix instead of the default
_fk
to
construct foreign key names. If you require a separator, such as an
underscore, between the name and the suffix, then you should include it into
the suffix value.
--sequence-suffix
suffix
- Use suffix instead of the default
_seq
to
construct sequence names. If you require a separator, such as an underscore,
between the name and the suffix, then you should include it into the suffix
value.
--sql-name-case
case
- Convert all automatically-derived SQL names to upper or lower case. Valid
values for this option are
upper
and
lower
.
--table-regex
regex
- Add regex to the list of regular expressions that is used to
transform automatically-derived table names. See the SQL NAME
TRANSFORMATIONS section below for details.
--column-regex
regex
- Add regex to the list of regular expressions that is used to
transform automatically-derived column names. See the SQL NAME
TRANSFORMATIONS section below for details.
--index-regex
regex
- Add regex to the list of regular expressions that is used to
transform automatically-derived index names. See the SQL NAME
TRANSFORMATIONS section below for details.
--fkey-regex
regex
- Add regex to the list of regular expressions that is used to
transform automatically-derived foreign key names. See the SQL NAME
TRANSFORMATIONS section below for details.
--sequence-regex
regex
- Add regex to the list of regular expressions that is used to
transform automatically-derived sequence names. See the SQL NAME
TRANSFORMATIONS section below for details.
--statement-regex
regex
- Add regex to the list of regular expressions that is used to
transform automatically-derived prepared statement names. See the SQL NAME
TRANSFORMATIONS section below for details.
--sql-name-regex
regex
- Add regex to the list of regular expressions that is used to
transform all automatically-derived SQL names. See the SQL NAME
TRANSFORMATIONS section below for details.
--sql-name-regex-trace
- Trace the process of applying regular expressions specified with the SQL
name
--*-regex
options. Use this option to find out why
your regular expressions don't do what you expected them to do.
--accessor-regex
regex
- Add regex to the list of regular expressions used to transform data
member names to function names when searching for a suitable accessor
function. The argument to this option is a Perl-like regular expression in
the form
/pattern/replacement/
. Any
character can be used as a delimiter instead of /
and
the delimiter can be escaped inside pattern
and
replacement
with a backslash (\
).
You can specify multiple regular expressions by repeating this option.
All the regular expressions are tried in the order specified and the
first expression that produces a suitable accessor function is used. Each
expression is tried twice: first with the actual member name and then with
the member's public name which is obtained by removing the common
member name decorations, such as leading and trailing underscores, the
m_
prefix, etc. The ODB compiler also includes a number
of built-in expressions for commonly used accessor names, such as
get_foo
, getFoo
,
getfoo
, and just foo
. The built-in
expressions are tried last.
As an example, the following expression transforms data members with
public names in the form foo
to accessor names in the
form GetFoo
:
/(.+)/Get\u$1/
See also the REGEX AND SHELL QUOTING section below.
--accessor-regex-trace
- Trace the process of applying regular expressions specified with the
--accessor-regex
option. Use this option to find out why
your regular expressions don't do what you expected them to do.
--modifier-regex
regex
- Add regex to the list of regular expressions used to transform data
member names to function names when searching for a suitable modifier
function. The argument to this option is a Perl-like regular expression in
the form
/pattern/replacement/
. Any
character can be used as a delimiter instead of /
and
the delimiter can be escaped inside pattern
and
replacement
with a backslash (\
).
You can specify multiple regular expressions by repeating this option.
All the regular expressions are tried in the order specified and the
first expression that produces a suitable modifier function is used. Each
expression is tried twice: first with the actual member name and then with
the member's public name which is obtained by removing the common
member name decorations, such as leading and trailing underscores, the
m_
prefix, etc. The ODB compiler also includes a number
of built-in expressions for commonly used modifier names, such as
set_foo
, setFoo
,
setfoo
, and just foo
. The built-in
expressions are tried last.
As an example, the following expression transforms data members with
public names in the form foo
to modifier names in the
form SetFoo
:
/(.+)/Set\u$1/
See also the REGEX AND SHELL QUOTING section below.
--modifier-regex-trace
- Trace the process of applying regular expressions specified with the
--modifier-regex
option. Use this option to find out why
your regular expressions don't do what you expected them to do.
--include-with-brackets
- Use angle brackets (<>) instead of quotes ("") in the generated
#include
directives.
--include-prefix
prefix
- Add prefix to the generated
#include
directive
paths.
--include-regex
regex
- Add regex to the list of regular expressions used to transform
generated
#include
directive paths. The argument to this
option is a Perl-like regular expression in the form
/pattern/replacement/
. Any
character can be used as a delimiter instead of /
and
the delimiter can be escaped inside pattern
and
replacement
with a backslash (\
).
You can specify multiple regular expressions by repeating this option. All
the regular expressions are tried in the order specified and the first
expression that matches is used.
As an example, the following expression transforms include paths in the
form foo/bar-odb.h
to paths in the form
foo/generated/bar-odb.h
:
%foo/(.+)-odb.h%foo/generated/$1-odb.h%
See also the REGEX AND SHELL QUOTING section below.
--include-regex-trace
- Trace the process of applying regular expressions specified with the
--include-regex
option. Use this option to find out why
your regular expressions don't do what you expected them to do.
--guard-prefix
prefix
- Add prefix to the generated header inclusion guards. The prefix is
transformed to upper case and characters that are illegal in a preprocessor
macro name are replaced with underscores.
--show-sloc
- Print the number of generated physical source lines of code (SLOC).
--sloc-limit
num
- Check that the number of generated physical source lines of code (SLOC) does
not exceed num.
--options-file
file
- Read additional options from file with each option appearing on a
separate line optionally followed by space and an option value. Empty lines
and lines starting with
#
are ignored. Option values can
be enclosed in double ("
) or single
('
) quotes to preserve leading and trailing whitespaces
as well as to specify empty values. If the value itself contains trailing or
leading quotes, enclose it with an extra pair of quotes, for example
'"x"'
. Non-leading and non-trailing quotes are
interpreted as being part of the option value.
The semantics of providing options in a file is equivalent to providing
the same set of options in the same order on the command line at the point
where the --options-file
option is specified except that
the shell escaping and quoting is not required. You can repeat this option
to specify more than one options file.
-x
option
- Pass option to the underlying C++ compiler (
g++
).
The option value that doesn't start with -
is
considered the g++
executable name.
-v
- Print the commands executed to run the stages of compilation.
--trace
- Trace the compilation process.
--mysql-engine
engine
- Use engine instead of the default
InnoDB
in the
generated database schema file. For more information on the storage engine
options see the MySQL documentation. If you would like to use the
database-default engine, pass default
as the value for
this option.
--sqlite-override-null
- Make all columns in the generated database schema allow
NULL
values. This is primarily useful in schema
migration since SQLite does not support dropping of columns. By making all
columns NULL
we can later "delete" them by setting their
values to NULL
. Note that this option overrides even the
not_null
pragma.
--sqlite-lax-auto-id
- Do not force monotonically increasing automatically-assigned object ids. In
this mode the generated database schema omits the
AUTOINCREMENT
keyword which results in faster object
persistence but may lead to automatically-assigned ids not being in a
strictly ascending order. Refer to the SQLite documentation for details.
--pgsql-server-version
ver
- Specify the minimum PostgreSQL server version with which the generated C++
code and schema will be used. This information is used to enable
version-specific optimizations and workarounds in the generated C++ code and
schema. The version must be in the
major.minor
form, for example,
9.1
. If this option is not specified, then
7.4
or later is assumed.
--oracle-client-version
ver
- Specify the minimum Oracle client library (OCI) version with which the
generated C++ code will be linked. This information is used to enable
version-specific optimizations and workarounds in the generated C++ code.
The version must be in the
major.minor
form, for example, 11.2
. If this option is not
specified, then 10.1
or later is assumed.
--oracle-warn-truncation
- Warn about SQL names that are longer than 30 characters and are therefore
truncated. Note that during database schema generation
(
--generate-schema
) ODB detects when such truncations
lead to name conflicts and issues diagnostics even without this option
specified.
--mssql-server-version
ver
- Specify the minimum SQL Server server version with which the generated C++
code and schema will be used. This information is used to enable
version-specific optimizations and workarounds in the generated C++ code and
schema. The version must be in the
major.minor
form, for example,
9.0
(SQL Server 2005), 10.5
(2008R2), or 11.0
(2012). If this option is not
specified, then 10.0
(SQL Server 2008) or later is
assumed.
--mssql-short-limit
size
- Specify the short data size limit. If a character, national character, or
binary data type has a maximum length (in bytes) less than or equal to this
limit, then it is treated as short data, otherwise it is long
data. For short data ODB pre-allocates an intermediate buffer of the
maximum size and binds it directly to a parameter or result column. This way
the underlying API (ODBC) can read/write directly from/to this buffer. In
the case of long data, the data is read/written in chunks using the
SQLGetData()
/SQLPutData()
ODBC
functions. While the long data approach reduces the amount of memory used by
the application, it may require greater CPU resources. The default short
data limit is 1024 bytes. When setting a custom short data limit, make sure
that it is sufficiently large so that no object id in the application is
treated as long data.
SQL NAME TRANSFORMATIONS
The ODB compiler provides a number of mechanisms for transforming
automatically-derived SQL names, such as tables, columns, etc.,
to match a specific naming convention. At the higher level, we can
add a prefix to global names (tables and, for some databases,
indexes and/or foreign keys) with the --table-prefix
option. Similarly, we can specify custom suffixes for
automatically-derived
index (--index-suffix
; default is _i
),
foreign key (--fkey-suffix
; default is _fk
), and
sequence (--sequence-suffix
; default is _seq
)
names. Finally, we can also convert all the names to upper or lower
case with the --sql-name-case
option (valid values
are upper
and lower
).
At the lower level we can specify a set of regular expressions to
implement arbitrary transformations of the automatically-derived SQL
names. If we want a particular regular expression only to apply to
a specific name, for example, table or column, then we use one of the
--kind-regex
options, where
kind
can be table
,
column
, index
,
fkey
, sequence
, or
statement
. On the other hand, if we want our
regular expressions to apply to all SQL names, then we use the
--sql-name-regex
option.
The interaction between the higher and lower level transformations
is as follows. Prefixes and suffixes are added first. Then the
regular expression transformations are applied. Finally, if requested,
the name is converted to upper or lower case. Note also that all of
these transformations except for --table-prefix
only apply to automatically-derived names. In other words, if a table,
column, etc., name was explicitly specified with a pragma, then it
is used as is, without applying any (except for the table prefix)
transformations.
The value for the --*-regex
options is a Perl-like
regular expression in the form
/pattern/replacement/
.
Any character can be used as a delimiter instead of /
and the delimiter can be escaped inside pattern
and
replacement
with a backslash (\
).
You can also specify multiple regular expressions by repeating these
options.
All the regular expressions are tried in the order specified with the
name-specific expressions (for example, --table-regex
)
tried first followed by the generic expressions
(--sql-name-regex
). The first expression that
matches is used.
As an example, consider a regular expression that transforms a class
name in the form CFoo
to a table name in the
form FOO
:
--table-regex '/C(.+)/\U$1/'
As a more interesting example, consider the transformation of class
names that follow the upper camel case convention (for example,
FooBar
) to table names that follow the
underscore-separated, all upper case convention (for example,
FOO_BAR
). For this case we have to use
separate expressions to handle one-word, two-word, etc.,
names:
--table-regex '/([A-z][a-z]+)/\U$1/'
--table-regex '/([A-z][a-z]+)([A-z][a-z]+)/\U$1_$2/'
See also the REGEX AND SHELL QUOTING section below.
REGEX AND SHELL QUOTING
When entering a regular expression argument in the shell
command line it is often necessary to use quoting (enclosing
the argument in " "
or
' '
) in order to prevent the shell
from interpreting certain characters, for example, spaces as
argument separators and $
as variable
expansions.
Unfortunately it is hard to achieve this in a manner that is
portable across POSIX shells, such as those found on
GNU/Linux and UNIX, and Windows shell. For example, if you
use " "
for quoting you will get a
wrong result with POSIX shells if your expression contains
$
. The standard way of dealing with this
on POSIX systems is to use ' '
instead.
Unfortunately, Windows shell does not remove ' '
from arguments when they are passed to applications. As a result you
may have to use ' '
for POSIX and
" "
for Windows ($
is
not treated as a special character on Windows).
Alternatively, you can save regular expression options into
a file, one option per line, and use this file with the
--options-file
option. With this approach
you don't need to worry about shell quoting.
DIAGNOSTICS
If the input file is not valid C++, odb
will issue diagnostic messages to STDERR and exit with non-zero exit
code.
BUGS
Send bug reports to the
odb-users@codesynthesis.com mailing list.