DEDECMS Two-time development: Dedesql.class.php Database Class

DEDECMS Two-time development directory point this:dedecms two-time development Tutorials Directory

The system will automatically load the dedesql.class.php file and use

$dsql = $db = new Dedesql (false);

The database connection is initialized, so there is no need to initialize the class separately in all the files in the project, which can be manipulated directly with the $dsql or $db, and to prevent errors, you do not have to close the database when you are done.

Common methods:

1, execute a non-query type of SQL statements, such as INSERT, create, update and so on

$rs = $db->executenonequery ($sql);

The return value is whether the execution was successful.

2. Executes a non-query-type SQL statement and returns the number of successful records

$rs = $db->executenonequery2 ($sql);

Compared to the above, it returns the number of records affected, not the Boolean value

3. Return a single record

$arr = $db->getone ($sql);

$dsql If you do not have a limit, the system automatically adds the limit 0,1

4. Execute Conditional Query statement

$db->setquery ($dsql), $db->execute (), while ($arr = $db->getarray ()) {} $db->setquery ($dsql), $db Execute (); while ($arr = $db->getarray ()) {}

Can be simplified to:

$db->execute (' Me ', $dsql), while ($arr = $db->getarray ()) {} $db->execute (' Me ', $dsql) and while ($arr = $db GetArray ()) {}

' Me ' is a recordset cursor that distinguishes between different queries, such as:

$db->execute (' Me ', $dsql), while ($arr = $db->getarray ()) {$db->execute (' 2 ', $dsql 2) and while ($arr 2 = $db GetArray ()) {}} $db->execute (' Me ', $dsql), while ($arr = $db->getarray ()) {$db->execute (' 2 ', $dsql 2); ARR2 = $db->getarray ()) {}}

In this case, you must specify a value to differentiate the default ' me ' parameter, or else an error will occur

$db->getarray ($rsid, $acctype) parameter $rsid= "Me" $acctype =mysql_assoc

Reading data in a query cursor can also be used

$db->getobject ($rsid = "Me");

The returned result is a value represented by the class structure.

5. Get the last inserted auto-increment primary Key ID value

$db->getlastid ();

6, the total number of records to obtain the query

$db->gettotalrow ($rsid = "Me")

7. Get the MySQL version number

$db->getversion ($isformat =true)

By default, it is converted to x.xx form floating point number

8. Analyze the resources of a query

$db->freeresult ($rsid = "Me");

9. If a data table exists in the database

$db->istable ($tbname)

10. Re-select the database you want to manipulate

$db->selectdb ($dbname);

11. Get the database connection ID

$db->linkid

Once you have this connection ID, you can perform database operations directly with MySQL related functions

In a non-forced situation, this variable is not normally used in the project.

DEDECMS Two-time development: Dedesql.class.php Database Class