ΚριτήριαAPIΑναφορά

ΟλοκληρώθηκεAPIτεκμηρίωση για τηνXOOPSΣύστημα δόμησης ερωτημάτων κριτηρίων.

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Κριτήρια Αρχιτεκτονική Συστήματος

classDiagram
    class CriteriaElement {
        <<abstract>>
        #string $order
        #string $sort
        #int $limit
        #int $start
        +setSort(sort)
        +getSort()
        +setOrder(order)
        +getOrder()
        +setLimit(limit)
        +getLimit()
        +setStart(start)
        +getStart()
        +setGroupby(groupby)
        +getGroupby()
        +render()
        +renderWhere()
        +renderLdap()
    }

    class Criteria {
        -string $prefix
        -string $function
        -string $column
        -string $operator
        -mixed $value
        +__construct(column, value, operator, prefix, function)
        +render()
        +renderWhere()
    }

    class CriteriaCompo {
        -array $criterias
        -array $conditions
        +__construct(criteria)
        +add(criteria, condition)
        +render()
        +renderWhere()
    }

    CriteriaElement <|-- Criteria
    CriteriaElement <|-- CriteriaCompo
    CriteriaCompo o-- CriteriaElement : contains

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Κατηγορία κριτηρίων

# Κατασκευαστής

public function __construct(
    string $column,           // Column name
    mixed $value = '',        // Value to compare
    string $operator = '=',   // Comparison operator
    string $prefix = '',      // Table prefix
    string $function = ''     // SQL function wrapper
)

# Χειριστές

Χειριστής	Παράδειγμα	SQLΈξοδος
=	new Criteria('status', 1)	status = 1
!=	new Criteria('status', 0, '!=')	status != 0
<>	new Criteria('status', 0, '<>')	status <> 0
<	new Criteria('age', 18, '<')	age < 18
<=	new Criteria('age', 18, '<=')	age <= 18
>	new Criteria('age', 18, '>')	age > 18
>=	new Criteria('age', 18, '>=')	age >= 18
LIKE	new Criteria('title', '%php%', 'LIKE')	title LIKE '%php%'
NOT LIKE	new Criteria('title', '%spam%', 'NOT LIKE')	title NOT LIKE '%spam%'
IN	new Criteria('id', '(1,2,3)', 'IN')	id IN (1,2,3)
NOT IN	new Criteria('id', '(1,2,3)', 'NOT IN')	id NOT IN (1,2,3)
IS NULL	new Criteria('deleted', null, 'IS NULL')	deleted IS NULL
IS NOT NULL	new Criteria('email', null, 'IS NOT NULL')	email IS NOT NULL
BETWEEN	new Criteria('created', '1000 AND 2000', 'BETWEEN')	created BETWEEN 1000 AND 2000

# Παραδείγματα χρήσης

// Simple equality
$criteria = new Criteria('status', 'published');

// Numeric comparison
$criteria = new Criteria('views', 100, '>=');

// Pattern matching
$criteria = new Criteria('title', '%XOOPS%', 'LIKE');

// With table prefix
$criteria = new Criteria('uid', 1, '=', 'u');
// Renders: u.uid = 1

// With SQL function
$criteria = new Criteria('title', '', '!=', '', 'LOWER');
// Renders: LOWER(title) != ''

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Κατηγορία CriteriaCompo

# Κατασκευαστής & Μέθοδοι

// Create empty compo
$criteria = new CriteriaCompo();

// Or with initial criteria
$criteria = new CriteriaCompo(new Criteria('status', 'active'));

// Add criteria (AND by default)
$criteria->add(new Criteria('views', 10, '>='));

// Add with OR
$criteria->add(new Criteria('featured', 1), 'OR');

// Nesting
$subCriteria = new CriteriaCompo();
$subCriteria->add(new Criteria('author', 1));
$subCriteria->add(new Criteria('author', 2), 'OR');
$criteria->add($subCriteria); // (author = 1 OR author = 2)

# Ταξινόμηση και σελιδοποίηση

$criteria = new CriteriaCompo();
$criteria->add(new Criteria('status', 'published'));

// Single sort
$criteria->setSort('created');
$criteria->setOrder('DESC');

// Multiple sort columns
$criteria->setSort('category_id, created');
$criteria->setOrder('ASC, DESC');

// Pagination
$criteria->setLimit(10);    // Items per page
$criteria->setStart(0);     // Offset (page * limit)

// Group by
$criteria->setGroupby('category_id');

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Ροή δημιουργίας ερωτημάτων

flowchart TD
    A[Create CriteriaCompo] --> B[Add Criteria]
    B --> C{More Conditions?}
    C -->|Yes| B
    C -->|No| D[Set Sort/Order]
    D --> E[Set Limit/Start]
    E --> F[Pass to Handler]
    F --> G[Handler calls render]
    G --> H[Generate SQL WHERE]
    H --> I[Execute Query]
    I --> J[Return Results]

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Παραδείγματα σύνθετων ερωτημάτων

# Αναζήτηση με πολλαπλές συνθήκες

$criteria = new CriteriaCompo();

// Status must be published
$criteria->add(new Criteria('status', 'published'));

// Category is 1, 2, or 3
$criteria->add(new Criteria('category_id', '(1, 2, 3)', 'IN'));

// Created in last 30 days
$thirtyDaysAgo = time() - (30 * 24 * 60 * 60);
$criteria->add(new Criteria('created', $thirtyDaysAgo, '>='));

// Search term in title OR content
$searchCriteria = new CriteriaCompo();
$searchCriteria->add(new Criteria('title', '%' . $searchTerm . '%', 'LIKE'));
$searchCriteria->add(new Criteria('content', '%' . $searchTerm . '%', 'LIKE'), 'OR');
$criteria->add($searchCriteria);

// Sort by views descending
$criteria->setSort('views');
$criteria->setOrder('DESC');

// Paginate
$criteria->setLimit($perPage);
$criteria->setStart($page * $perPage);

// Execute
$items = $itemHandler->getObjects($criteria);
$total = $itemHandler->getCount($criteria);

# Ερώτημα εύρους ημερομηνιών

$criteria = new CriteriaCompo();

// Between two dates
$startDate = strtotime('2024-01-01');
$endDate = strtotime('2024-12-31');

$criteria->add(new Criteria('created', $startDate, '>='));
$criteria->add(new Criteria('created', $endDate, '<='));

// Or using BETWEEN
$criteria->add(new Criteria('created', "$startDate AND $endDate", 'BETWEEN'));

# Φίλτρο δικαιωμάτων χρήστη

$criteria = new CriteriaCompo();
$criteria->add(new Criteria('status', 'published'));

// If not admin, only show own items or public
if (!$xoopsUser || !$xoopsUser->isAdmin()) {
    $permCriteria = new CriteriaCompo();
    $permCriteria->add(new Criteria('visibility', 'public'));

    if (is_object($xoopsUser)) {
        $permCriteria->add(new Criteria('author_id', $xoopsUser->getVar('uid')), 'OR');
    }

    $criteria->add($permCriteria);
}

# Ερώτημα τύπου συμμετοχής

// Get items where category is active
// (Using subquery approach)
$categoryHandler = xoops_getHandler('category');
$activeCatCriteria = new Criteria('status', 'active');
$activeCategories = $categoryHandler->getIds($activeCatCriteria);

if (!empty($activeCategories)) {
    $criteria->add(new Criteria('category_id', '(' . implode(',', $activeCategories) . ')', 'IN'));
}

---

Κριτήρια για ναSQLΟραματισμός

graph LR
    subgraph "PHP Code"
        A["new Criteria('status', 'published')"]
        B["new Criteria('views', 100, '>=')"]
        C["CriteriaCompo with A + B"]
    end

    subgraph "Generated SQL"
        D["status = 'published'"]
        E["views >= 100"]
        F["WHERE status = 'published' AND views >= 100"]
    end

    A --> D
    B --> E
    C --> F

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Ενσωμάτωση χειριστή

// Standard handler methods that accept Criteria

// Get multiple objects
$objects = $handler->getObjects($criteria);
$objects = $handler->getObjects($criteria, true);  // As array
$objects = $handler->getObjects($criteria, true, true); // As array, id as key

// Get count
$count = $handler->getCount($criteria);

// Get list (id => identifier)
$list = $handler->getList($criteria);

// Delete matching
$deleted = $handler->deleteAll($criteria);

// Update matching
$handler->updateAll('status', 'archived', $criteria);

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Θέματα απόδοσης

graph TB
    subgraph "Optimization Tips"
        A[Use Indexes] --> E[Faster Queries]
        B[Limit Results] --> E
        C[Avoid LIKE '%...'] --> E
        D[Use Specific Columns] --> E
    end

    subgraph "Anti-Patterns"
        F[No Indexes] --> G[Slow Queries]
        H[SELECT *] --> G
        I[No LIMIT] --> G
        J[Leading Wildcards] --> G
    end

# Βέλτιστες πρακτικές

1. Πάντα ρυθμισμένοLIMIT για μεγάλα τραπέζια
2. Χρησιμοποιήστε ευρετήρια σε στήλες που χρησιμοποιούνται στα κριτήρια
3. Αποφύγετε τους οδηγούς μπαλαντέρ μέσαLIKE ('%term' είναι αργός)
4. ΠροφιλτράρετεPHP όταν είναι δυνατόν για σύνθετη λογική
5. ΧρήσηCOUNTμε φειδώ - αποτελέσματα προσωρινής αποθήκευσης όταν είναι δυνατόν

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Σχετική τεκμηρίωση

• Επίπεδο βάσης δεδομένων
• XoopsObjectHandlerAPI
• SQLΠρόληψη ενέσεων

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XOOPS #api #criteria #βάση δεδομένων #ερώτημα #αναφορά