SQLite3

简介
安装／配置
- 需求
- 安装
- 运行时配置
- 资源类型
预定义常量
SQLite3 — SQLite3 类
- SQLite3::busyTimeout — Sets the busy connection handler
- SQLite3::changes — Returns the number of database rows that were changed (or inserted or deleted) by the most recent SQL statement
- SQLite3::close — Closes the database connection
- SQLite3::__construct — Instantiates an SQLite3 object and opens an SQLite 3 database
- SQLite3::createAggregate — Registers a PHP function for use as an SQL aggregate function
- SQLite3::createCollation — Registers a PHP function for use as an SQL collating function
- SQLite3::createFunction — Registers a PHP function for use as an SQL scalar function
- SQLite3::escapeString — Returns a string that has been properly escaped
- SQLite3::exec — Executes a result-less query against a given database
- SQLite3::lastErrorCode — Returns the numeric result code of the most recent failed SQLite request
- SQLite3::lastErrorMsg — Returns English text describing the most recent failed SQLite request
- SQLite3::lastInsertRowID — Returns the row ID of the most recent INSERT into the database
- SQLite3::loadExtension — Attempts to load an SQLite extension library
- SQLite3::open — Opens an SQLite database
- SQLite3::prepare — Prepares an SQL statement for execution
- SQLite3::query — Executes an SQL query
- SQLite3::querySingle — Executes a query and returns a single result
- SQLite3::version — Returns the SQLite3 library version as a string constant and as a number
SQLite3Stmt — SQLite3Stmt 类
- SQLite3Stmt::bindParam — Binds a parameter to a statement variable
- SQLite3Stmt::bindValue — Binds the value of a parameter to a statement variable
- SQLite3Stmt::clear — Clears all current bound parameters
- SQLite3Stmt::close — Closes the prepared statement
- SQLite3Stmt::execute — Executes a prepared statement and returns a result set object
- SQLite3Stmt::paramCount — Returns the number of parameters within the prepared statement
- SQLite3Stmt::reset — Resets the prepared statement
SQLite3Result — SQLite3Result 类
- SQLite3Result::columnName — Returns the name of the nth column
- SQLite3Result::columnType — Returns the type of the nth column
- SQLite3Result::fetchArray — Fetches a result row as an associative or numerically indexed array or both
- SQLite3Result::finalize — Closes the result set
- SQLite3Result::numColumns — Returns the number of columns in the result set
- SQLite3Result::reset — Resets the result set back to the first row

用户评论:

[#1] bohwaz [2014-04-21 00:47:00]

Another undocumented feature of the PHP SQLite3 object, available since 2009 is openBlob. Basically it's a function that will return a stream pointer to a blob value in a table. Very very useful when you are dealing with files stored in a SQLite3 database.

Source code says:

proto resource SQLite3::openBlob(string table, string column, int rowid [, string dbname])
Open a blob as a stream which we can read / write to.

But despite that it's not possible to write to the blob, only to read (the write method is empty in the extension source code: it won't return any error but no change will be recorded).

One example of use:

<?php $db = new SQLite3('files.sqlite'); $db->exec('CREATE TABLE files (id INTEGER PRIMARY KEY, filename TEXT, content BLOB);'); $statement = $db->prepare('INSERT INTO files (filename, content) VALUES (?, ?);'); $statement->bindValue('filename', 'Archive.zip'); $statement->bindValue('content', file_get_contents('Archive.zip')); $statement->execute(); $fp = $db->openBlob('files', 'content', $id); while (!feof($fp)) { echo fgets($fp); } fclose($fp); ?>

You can also seek in the stream. This is pretty useful for saving large files from the database too, this way you can use stream_copy_to_stream, it will be faster and more memory-efficient than dumping the file in memory before writing it to the disk.

Please note that openBlob() won't work on VIRTUAL FTS4 compressed tables.

[#2] bohwaz [2013-09-05 04:10:45]

As reported here: https://bugs.php.net/bug.php?id=65216 there are two undocumented and useful methods available:

SQLite3::createCollation(collation name, callback function) appeared in PHP 5.3.11 and allows to define a custom collation method.

SQLite3Stmt::readOnly(void) appeared in PHP 5.3.5 and returns true if a statement doesn't write in the database.

See the documentation pages on the corresponding classes for my comments showing example use of those methods.

[#3] Anonymous [2011-12-06 00:56:46]

As of PHP 5.4 support for Sqlite2 has been removed. I have a large web app that was built with sqlite2 as the database backend and thus it exploded when I updated PHP. If you're in a similar situation I've written a few wrapper functions that will allow your app to work whilst you convert the code to sqlite3.

Firstly convert your DB to an sqlite3 db.

sqlite OLD.DB .dump | sqlite3 NEW.DB

Then add the following functions to your app:

<?php function sqlite_open($location,$mode) { $handle = new SQLite3($location); return $handle; } function sqlite_query($dbhandle,$query) { $array['dbhandle'] = $dbhandle; $array['query'] = $query; $result = $dbhandle->query($query); return $result; } function sqlite_fetch_array(&$result,$type) { #Get Columns $i = 0; while ($result->columnName($i)) { $columns[ ] = $result->columnName($i); $i++; } $resx = $result->fetchArray(SQLITE3_ASSOC); return $resx; } ?>

They're not perfect by any stretch but they seem to be working ok as a temporary measure while I convert the site.
Hope that helps someone

[#4] alan at chandlerfamily dot org dot uk [2010-08-09 01:36:53]

PHP 5.3.3 introduced sqlite3::busyTimeout(int milliseconds) which does not currently seem to be documented.

It believe it acts like sqlite::busyTimeout - that is it tells sqlite3 to call an internal busyHandler if SQLITE_BUSY is returned from any call which waits a short period and then retries. It continues to do this until milliseconds milliseconds have elapsed and then returns the SQLITE_BUSY status.

I don't know whether the default 60 second value is in place if this function is not called.