(PHP 4, PHP 5, PHP 7, PHP 8)
dba_popen — Open database persistently
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.
args
Optional string parameters which are passed to the driver.
The cdb
, cdb_make
, flatfile
,
inifile
, qdbm
and tcadb
drivers
do not support additional parameters.
The db1
, db2
, db3
,
db4
, dbm
, gdbm
,
and ndbm
drivers supports a single additional parameter $filemode
,
which has the same meaning as the $mode
parameter of chmod(),
and defaults to 0644
.
The lmdb
driver accepts two additional parameters. The first
allows to specify the $filemode
(see description above), and the
second to specify the $mapsize
, where the value should be a multiple
of the page size of the OS, or zero, to use the default mapsize. The $mapsize
parameter is supported as of PHP 7.3.14 and 7.4.2, respectively.
Returns a positive handle on success 或者在失败时返回 false
.