(PHP 4, PHP 5, PHP 7, PHP 8)
dba_popen — Open database persistently
$path
,$mode
,$handler
= null
,$permission
= 0644,$map_size
= 0,$flags
= null
dba_popen() establishes a persistent database instance
for path
with mode
using
handler
.
path
Commonly a regular path in your filesystem.
mode
It is r
for read access, w
for
read/write access to an already existing database, c
for read/write access and database creation if it doesn't currently exist,
and n
for create, truncate and read/write access.
handler
The name of the handler which
shall be used for accessing path
. It is passed
all optional parameters given to dba_popen() and
can act on behalf of them. If handler
is null
,
then the default handler is invoked.
permission
Optional int parameter which is passed to the driver. It has the same meaning as
the permissions
parameter of chmod(),
and defaults to 0644
.
The db1
, db2
, db3
,
db4
, dbm
, gdbm
,
ndbm
, and lmdb
drivers support the
permission
parameter.
map_size
Optional int parameter which is passed to the driver. Its value should be a multiple of the page size of the OS, or zero, to use the default mapsize.
The lmdb
driver accepts the map_size
parameter.
flags
Allows to pass flags to the DB drivers. Currently, only LMDB with
DBA_LMDB_USE_SUB_DIR
and DBA_LMDB_NO_SUB_DIR
are supported.
Returns a positive handle on success 或者在失败时返回 false
.
false
is returned and an E_WARNING
level error is issued when
handler
is null
, but there is no default handler.
版本 | 说明 |
---|---|
8.2.0 |
flags is added.
|
8.1.0 |
handler is now nullable.
|
7.3.14, 7.4.2 |
The lmdb driver now supports an additional map_size
parameter.
|