Pramnos QueryBuilder Guide¶
The QueryBuilder provides a fluent, dialect-aware interface for constructing SQL queries programmatically. It automatically handles dialect differences between MySQL, PostgreSQL, and TimescaleDB, and supports advanced features like window functions, subqueries, and set operations.
Class: Pramnos\Database\QueryBuilder
Entry point: $db->queryBuilder() — returns a fresh builder bound to the current database connection.
Foundational Concepts¶
Read/Write Replicas¶
Applications that scale horizontally typically run one primary database for writes and one or more read replicas for SELECT queries. The Database class maintains separate read and write connections, automatically routing queries based on their type.
Configuration¶
Add read and write blocks to your settings.php:
'database' => [
'type' => 'mysql',
'write' => [
'hostname' => 'db-primary.example.com',
'user' => 'app_rw',
'password' => 'secret',
'database' => 'myapp',
],
'read' => [
'hostname' => 'db-replica.example.com',
'user' => 'app_ro',
'password' => 'secret',
'database' => 'myapp',
],
'port' => 3306,
'prefix' => 'pramnos_',
'collation' => 'utf8mb4_unicode_ci',
]
PostgreSQL / TimescaleDB works identically:
'database' => [
'type' => 'postgresql',
'write' => ['hostname' => 'pg-primary', 'user' => 'app', 'password' => '...', 'database' => 'myapp'],
'read' => ['hostname' => 'pg-replica', 'user' => 'app', 'password' => '...', 'database' => 'myapp'],
'schema' => 'public',
]
How Routing Works¶
Database::isWriteQuery(string $sql): bool checks the first SQL keyword. Queries beginning with SELECT, SHOW, EXPLAIN, DESC, or DESCRIBE are treated as reads; everything else as a write.
$db = \Pramnos\Database\Database::getInstance();
// Automatically uses the READ connection
$result = $db->query("SELECT * FROM #PREFIX#users WHERE active = 1");
// Automatically uses the WRITE connection
$db->query("UPDATE #PREFIX#users SET last_login = NOW() WHERE userid = %i", 42);
API Reference¶
| Method | Description |
|---|---|
getConnection(bool $isWrite = false) |
Returns the appropriate live connection, reconnecting if needed |
isConnectionAlive(mixed $connection): bool |
Checks if connection handle is open |
isWriteQuery(string $sql): bool |
Returns true if the query's first keyword implies a write operation |
BC Note: If read/write config keys are absent, the database behaves as before — a single connection for all queries.
Connection Health & Auto-reconnect¶
Long-running workers and daemon processes lose database connections when the server closes idle sockets (e.g., MySQL's wait_timeout). Previously this caused silent failures; now Database::query() detects a lost connection and transparently reconnects once before executing.
How It Works¶
On each query, if the connection is dead, the framework calls tryReconnect() before executing SQL. If reconnect succeeds, the query runs normally. If it fails, the original exception propagates.
API Reference¶
| Method | Description |
|---|---|
tryReconnect(): bool |
Non-fatal reconnect. Returns true on success, false on failure |
refresh(bool $throwOnFailure = true): bool |
Full reconnect. Throws RuntimeException on failure if $throwOnFailure is true |
isConnectionAlive(mixed $connection): bool |
Low-level check used internally |
Usage¶
For most applications, reconnect is fully automatic — no code changes needed:
// Normal query — transparently reconnects if connection dropped
$result = $db->query('SELECT * FROM users WHERE active = 1');
For long-running daemons that want to pro-actively verify before a critical operation:
// Non-fatal check (returns bool)
if (!$db->tryReconnect()) {
$logger->warning('Database unavailable, skipping this cycle');
sleep(5);
continue;
}
For workers that should abort on connection failure:
DatabaseCapabilities — Runtime Detection¶
Features like JSONB, TimescaleDB hypertables, and spatial indexes are not available on every backend. DatabaseCapabilities detects the connected server's actual capabilities at runtime and provides a clean API to branch on them.
Class: Pramnos\Database\DatabaseCapabilities
Getting Started¶
$db = \Pramnos\Database\Database::getInstance();
$caps = new \Pramnos\Database\DatabaseCapabilities($db);
if ($caps->hasTimescaleDB()) {
// use time_bucket(), hypertable APIs
} elseif ($caps->isPostgreSQL()) {
// plain PostgreSQL fallback
} else {
// MySQL fallback
}
Conditional Execution with ifCapable()¶
$caps->ifCapable(
\Pramnos\Database\DatabaseCapabilities::FEATURE_TIMESCALEDB,
function () use ($db, $table) {
// runs only on TimescaleDB
$db->query("SELECT create_hypertable('%s', 'time')", $table);
},
function () {
// runs on all other backends
}
);
Feature Constants¶
| Constant | Value | Detected via |
|---|---|---|
FEATURE_TIMESCALEDB |
'timescaledb' |
pg_extension catalog query |
FEATURE_JSON |
'json' |
Always true (MySQL 5.7+, all PG versions) |
FEATURE_JSONB |
'jsonb' |
PostgreSQL only |
FEATURE_FULLTEXT |
'fulltext' |
MySQL only |
FEATURE_SPATIAL |
'spatial' |
MySQL with spatial extensions |
API Reference¶
has(string $capability): bool— Returnstrueif capability is supportedisMySQL(): bool— Returnstruefor MySQLisPostgreSQL(): bool— Returnstruefor PostgreSQL and TimescaleDBhasTimescaleDB(): bool— Returnstrueonly if TimescaleDB extension is loadedifCapable(string $capability, callable $ifTrue, ?callable $ifFalse = null): mixed— Executes callback based on capabilitysupports(string $capability): bool— Fluent alias forhas()
Getting Started¶
Basic Patterns¶
$db = \Pramnos\Database\Database::getInstance();
// SELECT with conditions
$activeUsers = $db->queryBuilder()
->from('users')
->where('active', 1)
->orderBy('created_at', 'desc')
->limit(10)
->get();
while ($activeUsers->fetch()) {
echo $activeUsers->fields['username'] . "\n";
}
// INSERT
$db->queryBuilder()
->table('users')
->insert(['username' => 'jane', 'email' => 'jane@example.com']);
// UPDATE
$db->queryBuilder()
->table('users')
->where('userid', 5)
->update(['active' => 0]);
// DELETE
$db->queryBuilder()
->from('users')
->where('active', 0)
->delete();
SELECT Queries¶
Column Selection¶
select(array|string $columns = ['*']): static¶
Sets the SELECT column list. Accepts individual strings, comma-separated strings, or an array.
// Select specific columns
$qb->select('userid', 'username', 'email');
// Array format with aliases
$qb->select(['u.userid', 'u.username', 'g.groupname']);
// SQL expressions
$qb->select('COUNT(*) as total');
// Raw expressions
$qb->select($qb->raw("TO_CHAR(created_at, 'YYYY-MM') as month"));
distinct(): static¶
Adds DISTINCT to the SELECT.
Table & Aliasing¶
from(string $table): static / table(string $table): static¶
Sets the FROM table with optional alias.
$qb->from('users');
$qb->from('users u'); // with alias
$qb->from('users AS u'); // explicit AS
// INSERT/UPDATE/DELETE prefer table()
$qb->table('users')->insert([...]);
WHERE Conditions¶
where(string $column, mixed $operator = null, mixed $value = null): static¶
Adds a WHERE condition. Supports multiple calling patterns:
// Two-argument: column = value (shorthand)
$qb->where('active', 1);
$qb->where('status', 'pending');
// Three-argument: column operator value
$qb->where('age', '>=', 18);
$qb->where('name', 'ILIKE', '%john%');
// Nested closure (parenthesized group)
$qb->where(function ($q) {
$q->where('status', 'active')->orWhere('role', 'admin');
});
// → WHERE (status = 'active' OR role = 'admin')
orWhere(...): static`¶
OR variant. Same calling conventions as where().
$qb->where('role', 'admin')->orWhere('role', 'superuser');
// → WHERE role = 'admin' OR role = 'superuser'
whereIn(string $column, array $values): static¶
$qb->whereIn('userid', [1, 2, 3]);
// → WHERE userid IN (1, 2, 3)
// Negation
$qb->whereIn('status', ['active', 'pending'], 'and', true);
// → WHERE status NOT IN ('active', 'pending')
whereNull(string $column): static / whereNotNull(string $column): static¶
whereBetween(string $column, array $values): static¶
whereRaw(string $sql, array $bindings = []): static¶
Raw WHERE clause for dialect-specific expressions.
$qb->whereRaw("LOWER(username) = %s", ['johndoe']);
$qb->whereRaw("ST_DWithin(geom, ST_MakePoint(%s, %s)::geography, 1000)", [23.72, 37.98]);
$qb->whereRaw("created_at > NOW() - INTERVAL '7 days'");
whereExists(Closure $callback): static¶
EXISTS subquery condition.
$result = $db->queryBuilder()
->from('products')
->whereExists(function (\Pramnos\Database\QueryBuilder $sub) {
$sub->select(['1'])
->from('order_items')
->whereRaw('order_items.product_id = products.id')
->whereRaw("order_items.status = 'pending'");
})
->get();
Joins¶
join(string $table, string $first, string $operator, string $second, string $type = 'inner'): static¶
$qb->join('orders o', 'o.userid', '=', 'u.userid');
// → INNER JOIN orders o ON o.userid = u.userid
$qb->join('roles r', 'r.roleid', '=', 'u.roleid', 'left');
// → LEFT JOIN roles r ON r.roleid = u.roleid
leftJoin(...), rightJoin(...), crossJoin(...)¶
Convenience methods:
$qb->leftJoin('profiles p', 'p.userid', '=', 'u.userid');
$qb->rightJoin('categories c', 'c.id', '=', 'p.category_id');
$qb->crossJoin('colors'); // CROSS JOIN (no ON clause)
joinRaw(string $sql): static¶
Ordering & Grouping¶
orderBy(string $column, string $direction = 'asc'): static¶
$qb->orderBy('created_at', 'desc');
$qb->orderBy('username'); // defaults to 'asc'
$qb->orderBy('id', 'asc')->orderBy('name', 'asc'); // multiple columns
latest(string $column = 'created_at'): static / oldest(...)¶
Shortcuts for orderBy(..., 'desc') and orderBy(..., 'asc').
groupBy(string|array $columns): static¶
having(string $column, mixed $operator = null, mixed $value = null): static¶
Same calling convention as where().
Pagination¶
limit(int $value) / offset(int $value): static¶
forPage(int $page, int $perPage = 15): static¶
Shorthand for offset(($page - 1) * $perPage)->limit($perPage).
$result = $db->queryBuilder()
->from('products')
->orderBy('name')
->forPage(3, 20) // page 3, 20 per page
->get();
Execution & Results¶
get(): Result¶
Compiles and executes the query.
first(): Result¶
Adds LIMIT 1 and executes.
$result = $qb->from('users')->where('username', 'jane')->first();
if ($result->numRows > 0) {
echo $result->fields['email'];
}
count(): int¶
Executes a COUNT(*) aggregate.
$total = $qb->from('users')->where('active', 1)->count();
// Pagination example
$qb = $db->queryBuilder()->from('orders')
->where('status', 1)
->orderBy('created_at', 'desc')
->limit(20)
->offset(40);
$total = $qb->count(); // Clones internally, strips ORDER BY/LIMIT/OFFSET
$rows = $qb->get();
Aggregates: sum(), avg(), min(), max()¶
$total = $qb->from('orders')->sum('amount');
$average = $qb->from('products')->avg('price');
$cheapest = $qb->from('products')->min('price');
$priciest = $qb->from('products')->max('price');
exists(): bool / doesntExist(): bool¶
if ($db->queryBuilder()->from('users')->where('email', $email)->exists()) {
throw new \RuntimeException('Email already registered');
}
if ($db->queryBuilder()->from('roles')->where('name', 'admin')->doesntExist()) {
// seed admin role
}
value(string $column): mixed / pluck(string $column): array¶
$email = $db->queryBuilder()->from('users')->where('userid', 42)->value('email');
$emails = $db->queryBuilder()->from('users')->where('active', 1)->pluck('email');
// → ['alice@example.com', 'bob@example.com', ...]
Advanced Features¶
Window Functions¶
$qb = $db->queryBuilder();
$result = $qb
->select([
'id', 'name', 'category', 'price',
$qb->over('RANK()', alias: 'price_rank',
partition: ['category'],
order: ['price' => 'asc']
),
])
->from('products')
->orderBy('category')
->get();
Supported functions: RANK(), DENSE_RANK(), ROW_NUMBER(), NTILE(), SUM(), AVG(), MIN(), MAX(), COUNT(), LAG(), LEAD(), FIRST_VALUE(), LAST_VALUE()
Subqueries¶
// As SELECT column (correlated)
$result = $db->queryBuilder()
->select(['userid', 'username'])
->selectSub(function ($sub) {
$sub->select('COUNT(*)')->from('orders')
->whereRaw('orders.userid = users.userid');
}, 'order_count')
->from('users')
->get();
// As FROM source (derived table)
$result = $db->queryBuilder()
->select(['category', 'avg_price'])
->fromSub(function ($sub) {
$sub->select(['category', $sub->raw('AVG(price) AS avg_price')])
->from('products')
->groupBy('category');
}, 'cat_avgs')
->where('avg_price', '>', 5.00)
->get();
Set Operations¶
// UNION (removes duplicates)
$active = $db->queryBuilder()->select('userid', 'email')->from('users')->where('active', 1);
$admins = $db->queryBuilder()->select('userid', 'email')->from('admin_users');
$result = $active->union($admins)->get();
// UNION ALL (keeps duplicates)
$q1 = $db->queryBuilder()->select('name')->from('buyers');
$q2 = $db->queryBuilder()->select('name')->from('sellers');
$result = $q1->unionAll($q2)->get();
Raw Expressions¶
$qb->select('userid', $qb->raw("TO_CHAR(created_at, 'YYYY-MM') as month"));
$qb->orderBy($qb->raw('COALESCE(last_login, created_at)'), 'desc');
$qb->update(['last_login' => $qb->raw('NOW()')]);
Conditional Building¶
$qb = $db->queryBuilder()->from('products');
// Adds WHERE only when $categoryId is set
$result = $qb->when($categoryId, fn($q) => $q->where('category_id', $categoryId))->get();
// With fallback
$result = $qb->when($sortField,
fn($q) => $q->orderBy($sortField),
fn($q) => $q->orderBy('created_at', 'desc')
)->get();
INSERT/UPDATE/DELETE¶
INSERT¶
$result = $db->queryBuilder()
->table('logs')
->insert([
'message' => 'User logged in',
'userid' => 42,
'created_at' => $qb->raw('NOW()'),
]);
UPDATE¶
$db->queryBuilder()
->table('users')
->where('userid', 42)
->update(['last_login' => $qb->raw('NOW()')]);
DELETE¶
TRUNCATE¶
Atomic Operations¶
// Increment
$db->queryBuilder()->from('posts')->where('postid', 123)->increment('views');
// Decrement
$db->queryBuilder()->from('wallets')->where('userid', 42)->decrement('balance', 9.99);
PostgreSQL RETURNING¶
// INSERT and get the new ID
$result = $db->queryBuilder()
->table('users')
->returning('userid')
->insert(['username' => 'jane', 'email' => 'jane@example.com']);
$newId = $result->fields['userid'];
// UPDATE and retrieve modified row
$result = $db->queryBuilder()
->table('users')
->where('userid', 5)
->returning(['userid', 'updated_at'])
->update(['active' => 0]);
Insert Variants¶
insertOrIgnore(array $values): Result¶
$db->queryBuilder()
->table('user_subscriptions')
->insertOrIgnore(['userid' => 42, 'topic' => 'alerts']);
// Second call with same keys does nothing — no exception
upsert(array $values, array $conflictColumns, array $updateValues = []): Result¶
$db->queryBuilder()
->table('user_settings')
->upsert(
['userid' => 5, 'setting_key' => 'theme', 'setting_value' => 'dark'],
['userid', 'setting_key'], // conflict target
['setting_value'] // columns to update on conflict
);
Batch Processing¶
Chunked Iteration¶
$db->queryBuilder()
->from('users')
->where('active', 1)
->orderBy('userid')
->chunk(500, function (array $rows, int $page) {
foreach ($rows as $user) {
sendWelcomeEmail($user['email']);
}
// return false here to stop early
});
Important: Always include
ORDER BYwithchunk(). Without deterministic ordering, rows may be skipped or duplicated.
Result Objects¶
get(), first(), and write operations return a Pramnos\Database\Result instance.
Cursor-based Iteration¶
$result = $qb->from('logs')->orderBy('logid', 'desc')->get();
while ($result->fetch()) {
echo $result->fields['message'] . "\n";
}
Fetch All At Once¶
Properties & Methods¶
| Property / Method | Description |
|---|---|
$result->fields |
Associative array of current row |
$result->numRows |
Total rows in result set |
$result->eof |
true once all rows read |
$result->getNumRows() |
Rows count (method form) |
$result->getAffectedRows() |
Rows affected by UPDATE/DELETE |
$result->getInsertId() |
Auto-increment ID from INSERT (MySQL) |
$result->fetchAll() |
All rows as array |
$result->fetch() |
Advance cursor |
$result->free() |
Free resource |
Debugging¶
toSql(): string¶
Returns compiled SQL without executing:
echo $qb->from('users')->where('active', 1)->toSql();
// → SELECT * FROM "users" WHERE "active" = '...'
getBindings(): array¶
Returns bound parameter values:
$bindings = $qb->from('users')->where('active', 1)->getBindings();
// → ['where' => [1], 'join' => [], ...]
Complete Example — Paginated List¶
$db = \Pramnos\Database\Database::getInstance();
$page = max(1, (int)($_GET['page'] ?? 1));
$perPage = 20;
$qb = $db->queryBuilder()
->select('u.userid', 'u.username', 'u.email', 'g.groupname')
->from('users u')
->leftJoin('usergroups g', 'g.groupid', '=', 'u.groupid')
->where('u.active', 1)
->orderBy('u.username')
->forPage($page, $perPage);
// count() clones internally — ORDER BY/LIMIT/OFFSET stripped automatically
$total = $qb->count();
$users = $qb->get()->fetchAll();
// Use $users and $total for rendering
Backward Compatibility¶
QueryBuilder is new and purely additive. The existing Database::query(), Database::prepareQuery(), and Database::execute() methods are unchanged and continue to work exactly as before. No migration required for existing code.