diff --git a/.gitignore b/.gitignore
index 62033b5..df06735 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,5 @@
+/test_*
+
 /.composer.lock.runphp
 
 .~lock*#
diff --git a/pgsql.php b/pgsql.php
deleted file mode 100644
index 918568f..0000000
--- a/pgsql.php
+++ /dev/null
@@ -1,81 +0,0 @@
-<?php
-require __DIR__.'/vendor/autoload.php';
-
-use nulib\cl;
-use nulib\db\Capacitor;
-use nulib\db\CapacitorChannel;
-use nulib\db\pgsql\Pgsql;
-use nulib\db\pgsql\PgsqlStorage;
-
-$pgsql = new Pgsql([
-  "host" => "pegase-dre.self",
-  "dbname" => "dre",
-  "user" => "root",
-  "password" => "admin",
-  #"user" => "reader",
-  #"password" => "reader",
-]);
-
-function e($sql) {
-  global $pgsql;
-  $v = $pgsql->exec($sql);
-  $v = var_export($v, true);
-  echo "'$sql' --> $v\n";
-}
-function g($sql) {
-  global $pgsql;
-  $v = $pgsql->get($sql);
-  $v = var_export($v, true);
-  echo "'$sql' --> $v\n";
-}
-function o($sql) {
-  global $pgsql;
-  $r = $pgsql->one($sql);
-  $r = var_export($r, true);
-  echo "'$sql' --> $r\n";
-}
-function a($sql) {
-  global $pgsql;
-  $rs = $pgsql->all($sql);
-  echo "'$sql'\n";
-  foreach ($rs as $r) {
-    $r = var_export($r, true);
-    echo "  --> $r\n";
-  }
-}
-
-g("select age from personnes where id=1");
-o("select name, age from personnes where id=2");
-a("select id, name, age from personnes");
-
-$n = rand();
-$pgsql->exec([
-  "insert",
-  "into" => "personnes",
-  "values" => [
-    "name" => "prout$n",
-    "age" => $n,
-  ],
-]);
-
-class MyChannel extends CapacitorChannel {
-  const COLUMN_DEFINITIONS = [
-    "name" => "varchar",
-    "value" => "int",
-  ];
-
-  function getItemValues($item): ?array {
-    return $item;
-  }
-}
-$storage = new PgsqlStorage($pgsql);
-$channel = new MyChannel();
-new Capacitor($storage, $channel);
-
-$channel->charge([
-  "name" => "one",
-  "value" => rand(),
-]);
-foreach ($channel->all(null) as $row) {
-  var_export($row);
-}
\ No newline at end of file
diff --git a/php/src/db/Capacitor.php b/php/src/db/Capacitor.php
index 70c6f46..aa5da52 100644
--- a/php/src/db/Capacitor.php
+++ b/php/src/db/Capacitor.php
@@ -120,10 +120,6 @@ class Capacitor implements ITransactor {
     if ($db->inTransaction()) $db->rollback();
   }
 
-  function getCreateSql(): string {
-    return $this->storage->_getCreateSql($this->channel);
-  }
-
   function exists(): bool {
     return $this->storage->_exists($this->channel);
   }
diff --git a/php/src/db/CapacitorChannel.php b/php/src/db/CapacitorChannel.php
index 97819d4..a17e679 100644
--- a/php/src/db/CapacitorChannel.php
+++ b/php/src/db/CapacitorChannel.php
@@ -17,6 +17,8 @@ class CapacitorChannel {
 
   const PRIMARY_KEYS = null;
 
+  const MIGRATION = null;
+
   const MANAGE_TRANSACTIONS = true;
 
   const EACH_COMMIT_THRESHOLD = 100;
@@ -80,6 +82,7 @@ class CapacitorChannel {
     }
     $this->columnDefinitions = $columnDefinitions;
     $this->primaryKeys = $primaryKeys;
+    $this->migration = cl::withn(static::MIGRATION);
   }
 
   protected string $name;
@@ -192,6 +195,12 @@ class CapacitorChannel {
     return $this->columnDefinitions;
   }
 
+  protected ?array $migration;
+
+  function getMigration(): ?array {
+    return $this->migration;
+  }
+
   protected ?array $primaryKeys;
 
   function getPrimaryKeys(): ?array {
diff --git a/php/src/db/CapacitorStorage.php b/php/src/db/CapacitorStorage.php
index 830e032..e2bc4ac 100644
--- a/php/src/db/CapacitorStorage.php
+++ b/php/src/db/CapacitorStorage.php
@@ -2,6 +2,7 @@
 namespace nulib\db;
 
 use nulib\cl;
+use nulib\db\_private\_migration;
 use nulib\db\cache\cache;
 use nulib\php\func;
 use nulib\ValueException;
@@ -75,6 +76,10 @@ abstract class CapacitorStorage {
     return cl::merge($definitions, $constraints);
   }
 
+  protected function getMigration(CapacitorChannel $channel): ?array {
+    return $channel->getMigration();
+  }
+
   /** sérialiser les valeurs qui doivent l'être dans $values */
   protected function serialize(CapacitorChannel $channel, ?array $values): ?array {
     if ($values === null) return null;
@@ -137,11 +142,10 @@ abstract class CapacitorStorage {
   }
 
   protected function _createSql(CapacitorChannel $channel): array {
-    $cols = $this->ColumnDefinitions($channel);
     return [
       "create table if not exists",
       "table" => $channel->getTableName(),
-      "cols" => $cols,
+      "cols" => $this->ColumnDefinitions($channel),
     ];
   }
 
@@ -156,12 +160,7 @@ $sql;
 EOT;
   }
 
-  abstract function _getCreateSql(CapacitorChannel $channel): string;
-
-  /** obtenir la requête SQL utilisée pour créer la table */
-  function getCreateSql(?string $channel): string {
-    return $this->_getCreateSql($this->getChannel($channel));
-  }
+  abstract function _getMigration(CapacitorChannel $channel): _migration;
 
   protected function _afterCreate(CapacitorChannel $channel): void {
   }
@@ -169,7 +168,7 @@ EOT;
   protected function _create(CapacitorChannel $channel): void {
     $channel->ensureSetup();
     if (!$channel->isCreated()) {
-      $this->db()->exec($this->_createSql($channel));
+      $this->_getMigration($channel)->migrate($this->db());
       $this->_afterCreate($channel);
       $channel->setCreated();
     }
diff --git a/php/src/db/_private/_create.php b/php/src/db/_private/_create.php
index 030c594..29e83eb 100644
--- a/php/src/db/_private/_create.php
+++ b/php/src/db/_private/_create.php
@@ -18,28 +18,36 @@ class _create extends _common {
 
   static function parse(array $query, ?array &$bindings=null): string {
     #XXX implémentation minimale
-    $sql = [self::merge_seq($query)];
+    $tmpsql = self::merge_seq($query);
+    self::consume('create(?:\s+table)?\b', $tmpsql);
+    $sql = ["create table"];
+    if ($tmpsql) $sql[] = $tmpsql;
 
     ## préfixe
-    if (($prefix = $query["prefix"] ?? null) !== null) $sql[] = $prefix;
+    $prefix = $query["prefix"] ?? null;
+    if ($prefix !== null) $sql[] = $prefix;
 
     ## table
-    $sql[] = $query["table"];
+    $table = $query["table"] ?? null;
+    if ($table !== null) $sql[] = $table;
 
     ## columns
-    $cols = $query["cols"];
-    $index = 0;
-    foreach ($cols as $col => &$definition) {
-      if ($col === $index) {
-        $index++;
-      } else {
-        $definition = "$col $definition";
-      }
-    }; unset($definition);
-    $sql[] = "(\n  ".implode("\n, ", $cols)."\n)";
+    $cols = $query["cols"] ?? null;
+    if ($cols !== null) {
+      $index = 0;
+      foreach ($cols as $col => &$definition) {
+        if ($col === $index) {
+          $index++;
+        } else {
+          $definition = "$col $definition";
+        }
+      }; unset($definition);
+      $sql[] = "(\n  ".implode("\n, ", $cols)."\n)";
+    }
 
     ## suffixe
-    if (($suffix = $query["suffix"] ?? null) !== null) $sql[] = $suffix;
+    $suffix = $query["suffix"] ?? null;
+    if ($suffix !== null) $sql[] = $suffix;
 
     ## fin de la requête
     return implode(" ", $sql);
diff --git a/php/src/db/_private/_delete.php b/php/src/db/_private/_delete.php
index fd78dbb..55409d9 100644
--- a/php/src/db/_private/_delete.php
+++ b/php/src/db/_private/_delete.php
@@ -17,13 +17,16 @@ class _delete extends _common {
     #XXX implémentation minimale
     $tmpsql = self::merge_seq($query);
     self::consume('delete(?:\s+from)?\b', $tmpsql);
-    $sql = ["delete from", $tmpsql];
+    $sql = ["delete from"];
+    if ($tmpsql) $sql[] = $tmpsql;
 
     ## préfixe
-    if (($prefix = $query["prefix"] ?? null) !== null) $sql[] = $prefix;
+    $prefix = $query["prefix"] ?? null;
+    if ($prefix !== null) $sql[] = $prefix;
 
     ## table
-    $sql[] = $query["from"];
+    $from = $query["from"] ?? null;
+    if ($from !== null) $sql[] = $from;
 
     ## where
     $where = $query["where"] ?? null;
@@ -36,7 +39,8 @@ class _delete extends _common {
     }
 
     ## suffixe
-    if (($suffix = $query["suffix"] ?? null) !== null) $sql[] = $suffix;
+    $suffix = $query["suffix"] ?? null;
+    if ($suffix !== null) $sql[] = $suffix;
 
     ## fin de la requête
     return implode(" ", $sql);
diff --git a/php/src/db/_private/_generic.php b/php/src/db/_private/_generic.php
index 1fef213..a2ec549 100644
--- a/php/src/db/_private/_generic.php
+++ b/php/src/db/_private/_generic.php
@@ -9,7 +9,7 @@ class _generic extends _common {
   ];
 
   static function isa(string $sql): bool {
-    return preg_match('/^(?:drop\s+table)\b/i', $sql);
+    return preg_match('/^drop\s+table\b/i', $sql);
   }
 
   static function parse(array $query, ?array &$bindings=null): string {
diff --git a/php/src/db/_private/_migration.php b/php/src/db/_private/_migration.php
new file mode 100644
index 0000000..8ad75a6
--- /dev/null
+++ b/php/src/db/_private/_migration.php
@@ -0,0 +1,45 @@
+<?php
+namespace nulib\db\_private;
+
+use nulib\db\IDatabase;
+use nulib\php\func;
+
+abstract class _migration {
+  const MIGRATION = null;
+
+  function __construct($migrations, string $channel="", ?IDatabase $db=null) {
+    $this->db = $db;
+    $this->channel = $channel;
+    if ($migrations === null) $migrations = static::MIGRATION;
+    if ($migrations === null) $migrations = [];
+    elseif (is_string($migrations)) $migrations = [$migrations];
+    elseif (is_callable($migrations)) $migrations = [$migrations];
+    elseif (!is_array($migrations)) $migrations = [strval($migrations)];
+    $this->migrations = $migrations;
+  }
+
+  protected ?IDatabase $db;
+
+  protected string $channel;
+
+  /** @var callable[]|string[]  */
+  protected $migrations;
+
+  abstract function setup(): void;
+  abstract function beforeMigrate(string $key): bool;
+  abstract function afterMigrate(string $key): void;
+
+  function migrate(?IDatabase $db=null): void {
+    $db = ($this->db ??= $db);
+    $this->setup();
+    foreach ($this->migrations as $key => $migration) {
+      if (!$this->beforeMigrate($key)) continue;
+      if (is_string($migration) || !func::is_callable($migration)) {
+        $db->exec($migration);
+      } else {
+        func::with($migration)->bind($this, true)->invoke([$db, $key]);
+      }
+      $this->afterMigrate($key);
+    }
+  }
+}
diff --git a/php/src/db/_private/_update.php b/php/src/db/_private/_update.php
index 97cf75d..7b297c4 100644
--- a/php/src/db/_private/_update.php
+++ b/php/src/db/_private/_update.php
@@ -21,10 +21,12 @@ class _update extends _common {
     $sql = [self::merge_seq($query)];
 
     ## préfixe
-    if (($prefix = $query["prefix"] ?? null) !== null) $sql[] = $prefix;
+    $prefix = $query["prefix"] ?? null;
+    if ($prefix !== null) $sql[] = $prefix;
 
     ## table
-    $sql[] = $query["table"];
+    $table = $query["table"] ?? null;
+    if ($table !== null) $sql[] = $table;
 
     ## set
     self::parse_set_values($query["values"], $setsql, $bindings);
@@ -42,7 +44,8 @@ class _update extends _common {
     }
 
     ## suffixe
-    if (($suffix = $query["suffix"] ?? null) !== null) $sql[] = $suffix;
+    $suffix = $query["suffix"] ?? null;
+    if ($suffix !== null) $sql[] = $suffix;
 
     ## fin de la requête
     return implode(" ", $sql);
diff --git a/php/src/db/mysql/MysqlStorage.php b/php/src/db/mysql/MysqlStorage.php
index 0c5e0f6..ced2c6f 100644
--- a/php/src/db/mysql/MysqlStorage.php
+++ b/php/src/db/mysql/MysqlStorage.php
@@ -23,7 +23,7 @@ class MysqlStorage extends CapacitorStorage {
   ];
 
   function _getCreateSql(CapacitorChannel $channel): string {
-    $query = new query($this->_createSql($channel));
+    $query = new _mysqlQuery($this->_createSql($channel));
     return self::format_sql($channel, $query->getSql());
   }
 
diff --git a/php/src/db/mysql/_mysqlQuery.php b/php/src/db/mysql/_mysqlQuery.php
new file mode 100644
index 0000000..83cfa1b
--- /dev/null
+++ b/php/src/db/mysql/_mysqlQuery.php
@@ -0,0 +1,7 @@
+<?php
+namespace nulib\db\mysql;
+
+use nulib\db\pdo\_pdoQuery;
+
+class _mysqlQuery extends _pdoQuery {
+}
diff --git a/php/src/db/mysql/query.php b/php/src/db/mysql/query.php
deleted file mode 100644
index 4b63677..0000000
--- a/php/src/db/mysql/query.php
+++ /dev/null
@@ -1,5 +0,0 @@
-<?php
-namespace nulib\db\mysql;
-
-class query extends \nulib\db\pdo\query {
-}
diff --git a/php/src/db/pdo/Pdo.php b/php/src/db/pdo/Pdo.php
index 091050a..2a970fa 100644
--- a/php/src/db/pdo/Pdo.php
+++ b/php/src/db/pdo/Pdo.php
@@ -22,7 +22,7 @@ class Pdo implements IDatabase {
         "dbconn" => $pdo->dbconn,
         "options" => $pdo->options,
         "config" => $pdo->config,
-        "migrate" => $pdo->migration,
+        "migration" => $pdo->migration,
       ], $params));
     } else {
       return new static($pdo, $params);
@@ -50,7 +50,7 @@ class Pdo implements IDatabase {
 
   protected const CONFIG = null;
 
-  protected const MIGRATE = null;
+  protected const MIGRATION = null;
 
   const dbconn_SCHEMA = [
     "name" => "string",
@@ -63,7 +63,7 @@ class Pdo implements IDatabase {
     "options" => ["?array|callable"],
     "replace_config" => ["?array|callable"],
     "config" => ["?array|callable"],
-    "migrate" => ["?array|string|callable"],
+    "migration" => ["?array|string|callable"],
     "auto_open" => ["bool", true],
   ];
 
@@ -94,7 +94,7 @@ class Pdo implements IDatabase {
     }
     $this->config = $config;
     # migrations
-    $this->migration = $params["migrate"] ?? static::MIGRATE;
+    $this->migration = $params["migration"] ?? static::MIGRATION;
     #
     $defaultAutoOpen = self::params_SCHEMA["auto_open"][1];
     if ($params["auto_open"] ?? $defaultAutoOpen) {
@@ -145,7 +145,7 @@ class Pdo implements IDatabase {
 
   function exec($query, ?array $params=null) {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _pdoQuery($query, $params);
     if ($query->_use_stmt($db, $stmt, $sql)) {
       if ($stmt->execute() === false) return false;
       if ($query->isInsert()) return $db->lastInsertId();
@@ -217,7 +217,7 @@ class Pdo implements IDatabase {
 
   function get($query, ?array $params=null, bool $entireRow=false) {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _pdoQuery($query, $params);
     $stmt = null;
     try {
       /** @var \PDOStatement $stmt */
@@ -242,7 +242,7 @@ class Pdo implements IDatabase {
 
   function all($query, ?array $params=null, $primaryKeys=null): iterable {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _pdoQuery($query, $params);
     $stmt = null;
     try {
       /** @var \PDOStatement $stmt */
diff --git a/php/src/db/pdo/query.php b/php/src/db/pdo/_pdoQuery.php
similarity index 95%
rename from php/src/db/pdo/query.php
rename to php/src/db/pdo/_pdoQuery.php
index 6fb05c9..c1161fa 100644
--- a/php/src/db/pdo/query.php
+++ b/php/src/db/pdo/_pdoQuery.php
@@ -5,7 +5,7 @@ use nulib\db\_private\_base;
 use nulib\db\_private\Tbindings;
 use nulib\output\msg;
 
-class query extends _base {
+class _pdoQuery extends _base {
   use Tbindings;
 
   const DEBUG_QUERIES = false;
diff --git a/php/src/db/pgsql/Pgsql.php b/php/src/db/pgsql/Pgsql.php
index 2fef081..b5bf9d8 100644
--- a/php/src/db/pgsql/Pgsql.php
+++ b/php/src/db/pgsql/Pgsql.php
@@ -21,7 +21,7 @@ class Pgsql implements IDatabase {
         "dbconn" => $pgsql->dbconn,
         "options" => $pgsql->options,
         "config" => $pgsql->config,
-        "migrate" => $pgsql->migration,
+        "migration" => $pgsql->migration,
       ], $params));
     } else {
       return new static($pgsql, $params);
@@ -37,14 +37,14 @@ class Pgsql implements IDatabase {
 
   const CONFIG = null;
 
-  const MIGRATE = null;
+  const MIGRATION = null;
 
   const params_SCHEMA = [
     "dbconn" => ["array"],
     "options" => ["?array|callable"],
     "replace_config" => ["?array|callable"],
     "config" => ["?array|callable"],
-    "migrate" => ["?array|string|callable"],
+    "migration" => ["?array|string|callable"],
     "auto_open" => ["bool", true],
   ];
 
@@ -95,7 +95,7 @@ class Pgsql implements IDatabase {
     }
     $this->config = $config;
     # migrations
-    $this->migration = $params["migrate"] ?? static::MIGRATE;
+    $this->migration = $params["migration"] ?? static::MIGRATION;
     #
     $defaultAutoOpen = self::params_SCHEMA["auto_open"][1];
     if ($params["auto_open"] ?? $defaultAutoOpen) {
@@ -183,7 +183,7 @@ class Pgsql implements IDatabase {
 
   function exec($query, ?array $params=null) {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _pgsqlQuery($query, $params);
     $result = $query->_exec($db);
     $serialSupport = $this->options["serial_support"] ?? true;
     if ($serialSupport && $query->isInsert()) return $this->getLastSerial();
@@ -261,7 +261,7 @@ class Pgsql implements IDatabase {
 
   function get($query, ?array $params=null, bool $entireRow=false) {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _pgsqlQuery($query, $params);
     $result = $query->_exec($db);
     $row = pg_fetch_assoc($result);
     pg_free_result($result);
@@ -277,7 +277,7 @@ class Pgsql implements IDatabase {
 
   function all($query, ?array $params=null, $primaryKeys=null): iterable {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _pgsqlQuery($query, $params);
     $result = $query->_exec($db);
     $primaryKeys = cl::withn($primaryKeys);
     while (($row = pg_fetch_assoc($result)) !== false) {
diff --git a/php/src/db/pgsql/PgsqlStorage.php b/php/src/db/pgsql/PgsqlStorage.php
index f47078a..419e043 100644
--- a/php/src/db/pgsql/PgsqlStorage.php
+++ b/php/src/db/pgsql/PgsqlStorage.php
@@ -24,7 +24,7 @@ class PgsqlStorage extends CapacitorStorage {
   ];
 
   function _getCreateSql(CapacitorChannel $channel): string {
-    $query = new query($this->_createSql($channel));
+    $query = new _pgsqlQuery($this->_createSql($channel));
     return self::format_sql($channel, $query->getSql());
   }
 
diff --git a/php/src/db/pgsql/query.php b/php/src/db/pgsql/_pgsqlQuery.php
similarity index 96%
rename from php/src/db/pgsql/query.php
rename to php/src/db/pgsql/_pgsqlQuery.php
index 3ab5b6d..34c7ed1 100644
--- a/php/src/db/pgsql/query.php
+++ b/php/src/db/pgsql/_pgsqlQuery.php
@@ -6,7 +6,7 @@ use nulib\db\_private\_base;
 use nulib\db\_private\Tbindings;
 use nulib\output\msg;
 
-class query extends _base {
+class _pgsqlQuery extends _base {
   use Tbindings;
 
   const DEBUG_QUERIES = false;
diff --git a/php/src/db/sqlite/Sqlite.php b/php/src/db/sqlite/Sqlite.php
index 4e22e11..fffb8f1 100644
--- a/php/src/db/sqlite/Sqlite.php
+++ b/php/src/db/sqlite/Sqlite.php
@@ -30,7 +30,7 @@ class Sqlite implements IDatabase {
         "encryption_key" => $sqlite->encryptionKey,
         "allow_wal" => $sqlite->allowWal,
         "config" => $sqlite->config,
-        "migrate" => $sqlite->migration,
+        "migration" => $sqlite->migration,
       ], $params));
     } elseif (is_array($sqlite)) {
       return new static(null, cl::merge($sqlite, $params));
@@ -72,7 +72,7 @@ class Sqlite implements IDatabase {
 
   const CONFIG = null;
 
-  const MIGRATE = null;
+  const MIGRATION = null;
 
   const params_SCHEMA = [
     "file" => ["string", ""],
@@ -81,7 +81,7 @@ class Sqlite implements IDatabase {
     "allow_wal" => ["?bool"],
     "replace_config" => ["?array|callable"],
     "config" => ["?array|callable"],
-    "migrate" => ["?array|string|callable"],
+    "migration" => ["?array|string|callable"],
     "auto_open" => ["bool", true],
   ];
 
@@ -109,7 +109,7 @@ class Sqlite implements IDatabase {
     }
     $this->config = $config;
     # migrations
-    $this->migration = $params["migrate"] ?? static::MIGRATE;
+    $this->migration = $params["migration"] ?? static::MIGRATION;
     #
     $defaultAutoOpen = self::params_SCHEMA["auto_open"][1];
     $this->inTransaction = false;
@@ -150,7 +150,7 @@ class Sqlite implements IDatabase {
     if ($this->db === null) {
       $this->db = new SQLite3($this->file, $this->flags, $this->encryptionKey);
       _config::with($this->config)->configure($this);
-      _migration::with($this->migration)->migrate($this);
+      _sqliteMigration::with($this->migration)->migrate($this);
       $this->inTransaction = false;
     }
     return $this;
@@ -183,7 +183,7 @@ class Sqlite implements IDatabase {
 
   function exec($query, ?array $params=null) {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _sqliteQuery($query, $params);
     if ($query->_use_stmt($db, $stmt, $sql)) {
       try {
         $result = $stmt->execute();
@@ -270,7 +270,7 @@ class Sqlite implements IDatabase {
 
   function get($query, ?array $params=null, bool $entireRow=false) {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _sqliteQuery($query, $params);
     if ($query->_use_stmt($db, $stmt, $sql)) {
       try {
         $result = $this->checkResult($stmt->execute());
@@ -315,7 +315,7 @@ class Sqlite implements IDatabase {
 
   function all($query, ?array $params=null, $primaryKeys=null): iterable {
     $db = $this->db();
-    $query = new query($query, $params);
+    $query = new _sqliteQuery($query, $params);
     if ($query->_use_stmt($db, $stmt, $sql)) {
       $result = $this->checkResult($stmt->execute());
       return $this->_fetchResult($result, $stmt, $primaryKeys);
diff --git a/php/src/db/sqlite/SqliteStorage.php b/php/src/db/sqlite/SqliteStorage.php
index d304d93..3ba97d6 100644
--- a/php/src/db/sqlite/SqliteStorage.php
+++ b/php/src/db/sqlite/SqliteStorage.php
@@ -1,6 +1,7 @@
 <?php
 namespace nulib\db\sqlite;
 
+use nulib\cl;
 use nulib\db\CapacitorChannel;
 use nulib\db\CapacitorStorage;
 
@@ -22,8 +23,14 @@ class SqliteStorage extends CapacitorStorage {
     "id_" => "integer primary key autoincrement",
   ];
 
+  function _getMigration(CapacitorChannel $channel): _sqliteMigration {
+    return new _sqliteMigration(cl::merge([
+      $this->_createSql($channel),
+    ], $channel->getMigration()), $channel->getName());
+  }
+
   function _getCreateSql(CapacitorChannel $channel): string {
-    $query = new query($this->_createSql($channel));
+    $query = new _sqliteQuery($this->_createSql($channel));
     return self::format_sql($channel, $query->getSql());
   }
 
@@ -51,8 +58,7 @@ class SqliteStorage extends CapacitorStorage {
       # ne pas créer si la table existe déjà, pour éviter d'avoir besoin d'un
       # verrou en écriture
       $sqlite->exec([
-        "create table if not exists",
-        "table" => "_channels",
+        "create table if not exists _channels",
         "cols" => [
           "name" => "varchar primary key",
           "table_name" => "varchar",
@@ -64,8 +70,7 @@ class SqliteStorage extends CapacitorStorage {
       # ne pas insérer si la ligne existe déjà, pour éviter d'avoir besoin d'un
       # verrou en écriture
       $sqlite->exec([
-        "insert",
-        "into" => "_channels",
+        "insert into _channels",
         "values" => [
           "name" => $channel->getName(),
           "table_name" => $channel->getTableName(),
@@ -77,9 +82,15 @@ class SqliteStorage extends CapacitorStorage {
   }
 
   protected function _beforeReset(CapacitorChannel $channel): void {
-    $this->sqlite->exec([
-      "delete",
-      "from" => "_channels",
+    $sqlite = $this->sqlite;
+    $sqlite->exec([
+      "delete from _migration",
+      "where" => [
+        "channel" => $channel->getName(),
+      ],
+    ]);
+    $sqlite->exec([
+      "delete from _channels",
       "where" => [
         "name" => $channel->getName(),
       ],
diff --git a/php/src/db/sqlite/_migration.php b/php/src/db/sqlite/_migration.php
deleted file mode 100644
index cafb991..0000000
--- a/php/src/db/sqlite/_migration.php
+++ /dev/null
@@ -1,54 +0,0 @@
-<?php
-namespace nulib\db\sqlite;
-
-use nulib\php\func;
-
-class _migration {
-  static function with($migrations): self {
-    if ($migrations instanceof static) {
-      return $migrations;
-    } elseif ($migrations instanceof self) {
-      return new static($migrations->migrations);
-    } else {
-      return new static($migrations);
-    }
-  }
-
-  const MIGRATE = null;
-
-  function __construct($migrations) {
-    if ($migrations === null) $migrations = static::MIGRATE;
-    if ($migrations === null) $migrations = [];
-    elseif (is_string($migrations)) $migrations = [$migrations];
-    elseif (is_callable($migrations)) $migrations = [$migrations];
-    elseif (!is_array($migrations)) $migrations = [strval($migrations)];
-    $this->migrations = $migrations;
-  }
-
-  /** @var callable[]|string[]  */
-  protected $migrations;
-  
-  function migrate(Sqlite $sqlite): void {
-    $sqlite->exec("create table if not exists _migration(key varchar primary key, value varchar not null, done integer default 0)");
-    foreach ($this->migrations as $key => $migration) {
-      $exists = $sqlite->get("select 1 from _migration where key = :key and done = 1", [
-        "key" => $key,
-      ]);
-      if (!$exists) {
-        $sqlite->exec("insert or replace into _migration(key, value, done) values(:key, :value, :done)", [
-          "key" => $key,
-          "value" => $migration,
-          "done" => 0,
-        ]);
-        if (is_string($migration) && !func::is_method($migration)) {
-          $sqlite->exec($migration);
-        } else {
-          func::with($migration)->bind($this, true)->invoke([$sqlite, $key]);
-        }
-        $sqlite->exec("update _migration set done = 1 where key = :key", [
-          "key" => $key,
-        ]);
-      }
-    }
-  }
-}
diff --git a/php/src/db/sqlite/_sqliteMigration.php b/php/src/db/sqlite/_sqliteMigration.php
new file mode 100644
index 0000000..1fdca37
--- /dev/null
+++ b/php/src/db/sqlite/_sqliteMigration.php
@@ -0,0 +1,57 @@
+<?php
+namespace nulib\db\sqlite;
+
+use nulib\db\_private\_migration;
+
+class _sqliteMigration extends _migration {
+  static function with($migration): self {
+    if ($migration instanceof self) return $migration;
+    else return new static($migration);
+  }
+
+  function setup(): void {
+    $this->db->exec([
+      "create table if not exists _migration",
+      "cols" => [
+        "channel" => "varchar not null",
+        "key" => "varchar not null",
+        "done" => "integer not null default 0",
+      ],
+    ]);
+  }
+
+  function beforeMigrate(string $key): bool {
+    $db = $this->db;
+    $migrated = $db->get([
+      "select 1 from _migration",
+      "where" => [
+        "channel" => $this->channel,
+        "key" => $key,
+        "done" => 1,
+      ],
+    ]);
+    if ($migrated) return false;
+    $db->exec([
+      "insert or replace into _migration",
+      "values" => [
+        "channel" => $this->channel,
+        "key" => $key,
+        "done" => 0,
+      ],
+    ]);
+    return true;
+  }
+
+  function afterMigrate(string $key): void {
+    $this->db->exec([
+      "update _migration",
+      "values" => [
+        "done" => 1,
+      ],
+      "where" => [
+        "channel" => $this->channel,
+        "key" => $key,
+      ],
+    ]);
+  }
+}
diff --git a/php/src/db/sqlite/query.php b/php/src/db/sqlite/_sqliteQuery.php
similarity index 97%
rename from php/src/db/sqlite/query.php
rename to php/src/db/sqlite/_sqliteQuery.php
index e8df936..14fb1b0 100644
--- a/php/src/db/sqlite/query.php
+++ b/php/src/db/sqlite/_sqliteQuery.php
@@ -14,7 +14,7 @@ use nulib\ValueException;
 use SQLite3;
 use SQLite3Stmt;
 
-class query extends _base {
+class _sqliteQuery extends _base {
   use Tbindings;
 
   const DEBUG_QUERIES = false;
diff --git a/php/src/php/func.php b/php/src/php/func.php
index 1309ec8..26361f7 100644
--- a/php/src/php/func.php
+++ b/php/src/php/func.php
@@ -437,7 +437,7 @@ class func {
     return new ValueException($reason);
   }
 
-  static function with($func, ?array $args=null, bool $strict=true): self {
+  private static function _with($func, ?array $args=null, bool $strict=true, ?string &$reason=null): ?self {
     if (!is_array($func)) {
       if ($func instanceof Closure) {
         return new self(self::TYPE_CLOSURE, $func, $args);
@@ -458,6 +458,12 @@ class func {
     } elseif (self::verifix_static($func, $strict, $bound, $reason)) {
       return new self(self::TYPE_STATIC, $func, $args, $bound, $reason);
     }
+    return null;
+  }
+
+  static function with($func, ?array $args=null, bool $strict=true): self {
+    $func = self::_with($func, $args, $strict, $reason);
+    if ($func !== null) return $func;
     throw self::not_a_callable($func, $reason);
   }
 
@@ -478,6 +484,13 @@ class func {
     }
   }
 
+  static function is_callable($func): bool {
+    $func = self::_with($func);
+    if ($func === null) return false;
+    if (!$func->isBound()) return false;
+    return $func->type !== self::TYPE_CLASS;
+  }
+
   static function call($func, ...$args) {
     return self::with($func)->invoke($args);
   }
@@ -638,7 +651,7 @@ class func {
 
   function bind($object, bool $unlessAlreadyBound=false, bool $replace=false): self {
     if ($this->type !== self::TYPE_METHOD) return $this;
-    if ($this->object !== null && $unlessAlreadyBound) return $this;
+    if ($this->bound && $unlessAlreadyBound) return $this;
 
     [$c, $f] = $this->func;
     if ($replace) {
diff --git a/php/tests/db/sqlite/SqliteTest.php b/php/tests/db/sqlite/SqliteTest.php
index b56855c..a6e23a1 100644
--- a/php/tests/db/sqlite/SqliteTest.php
+++ b/php/tests/db/sqlite/SqliteTest.php
@@ -11,7 +11,7 @@ class SqliteTest extends TestCase {
 
   function testMigration() {
     $sqlite = new Sqlite(":memory:", [
-      "migrate" => [
+      "migration" => [
         self::CREATE_PERSON,
         self::INSERT_JEPHTE,
       ],
@@ -49,7 +49,7 @@ class SqliteTest extends TestCase {
   }
   function testInsert() {
     $sqlite = new Sqlite(":memory:", [
-      "migrate" => "create table mapping (i integer, s varchar)",
+      "migration" => "create table mapping (i integer, s varchar)",
     ]);
     $sqlite->exec(["insert into mapping", "values" => ["i" => 1, "s" => "un"]]);
     $sqlite->exec(["insert mapping", "values" => ["i" => 2, "s" => "deux"]]);
@@ -78,7 +78,7 @@ class SqliteTest extends TestCase {
 
   function testSelect() {
     $sqlite = new Sqlite(":memory:", [
-      "migrate" => "create table user (name varchar, amount integer)",
+      "migration" => "create table user (name varchar, amount integer)",
     ]);
     $sqlite->exec(["insert into user", "values" => ["name" => "jclain1", "amount" => 1]]);
     $sqlite->exec(["insert into user", "values" => ["name" => "jclain2", "amount" => 2]]);
@@ -130,7 +130,7 @@ class SqliteTest extends TestCase {
 
   function testSelectGroupBy() {
     $sqlite = new Sqlite(":memory:", [
-      "migrate" => "create table user (name varchar, amount integer)",
+      "migration" => "create table user (name varchar, amount integer)",
     ]);
     $sqlite->exec(["insert into user", "values" => ["name" => "jclain1", "amount" => 1]]);
     $sqlite->exec(["insert into user", "values" => ["name" => "jclain2", "amount" => 1]]);
diff --git a/php/tests/db/sqlite/_queryTest.php b/php/tests/db/sqlite/_queryTest.php
index 3337eb5..3d069dd 100644
--- a/php/tests/db/sqlite/_queryTest.php
+++ b/php/tests/db/sqlite/_queryTest.php
@@ -6,119 +6,119 @@ use PHPUnit\Framework\TestCase;
 class _queryTest extends TestCase {
   function testParseConds(): void {
     $sql = $params = null;
-    query::parse_conds(null, $sql, $params);
+    _sqliteQuery::parse_conds(null, $sql, $params);
     self::assertNull($sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_conds([], $sql, $params);
+    _sqliteQuery::parse_conds([], $sql, $params);
     self::assertNull($sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_conds(["col" => null], $sql, $params);
+    _sqliteQuery::parse_conds(["col" => null], $sql, $params);
     self::assertSame(["col is null"], $sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_conds(["col = 'value'"], $sql, $params);
+    _sqliteQuery::parse_conds(["col = 'value'"], $sql, $params);
     self::assertSame(["col = 'value'"], $sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_conds([["col = 'value'"]], $sql, $params);
+    _sqliteQuery::parse_conds([["col = 'value'"]], $sql, $params);
     self::assertSame(["col = 'value'"], $sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_conds(["int" => 42, "string" => "value"], $sql, $params);
+    _sqliteQuery::parse_conds(["int" => 42, "string" => "value"], $sql, $params);
     self::assertSame(["(int = :int and string = :string)"], $sql);
     self::assertSame(["int" => 42, "string" => "value"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["or", "int" => 42, "string" => "value"], $sql, $params);
+    _sqliteQuery::parse_conds(["or", "int" => 42, "string" => "value"], $sql, $params);
     self::assertSame(["(int = :int or string = :string)"], $sql);
     self::assertSame(["int" => 42, "string" => "value"], $params);
 
     $sql = $params = null;
-    query::parse_conds([["int" => 42, "string" => "value"], ["int" => 24, "string" => "eulav"]], $sql, $params);
+    _sqliteQuery::parse_conds([["int" => 42, "string" => "value"], ["int" => 24, "string" => "eulav"]], $sql, $params);
     self::assertSame(["((int = :int and string = :string) and (int = :int2 and string = :string2))"], $sql);
     self::assertSame(["int" => 42, "string" => "value", "int2" => 24, "string2" => "eulav"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["int" => ["is null"], "string" => ["<>", "value"]], $sql, $params);
+    _sqliteQuery::parse_conds(["int" => ["is null"], "string" => ["<>", "value"]], $sql, $params);
     self::assertSame(["(int is null and string <> :string)"], $sql);
     self::assertSame(["string" => "value"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["col" => ["between", "lower", "upper"]], $sql, $params);
+    _sqliteQuery::parse_conds(["col" => ["between", "lower", "upper"]], $sql, $params);
     self::assertSame(["col between :col and :col2"], $sql);
     self::assertSame(["col" => "lower", "col2" => "upper"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["col" => ["in", "one"]], $sql, $params);
+    _sqliteQuery::parse_conds(["col" => ["in", "one"]], $sql, $params);
     self::assertSame(["col in (:col)"], $sql);
     self::assertSame(["col" => "one"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["col" => ["in", ["one", "two"]]], $sql, $params);
+    _sqliteQuery::parse_conds(["col" => ["in", ["one", "two"]]], $sql, $params);
     self::assertSame(["col in (:col, :col2)"], $sql);
     self::assertSame(["col" => "one", "col2" => "two"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["col" => ["=", ["one", "two"]]], $sql, $params);
+    _sqliteQuery::parse_conds(["col" => ["=", ["one", "two"]]], $sql, $params);
     self::assertSame(["col = :col and col = :col2"], $sql);
     self::assertSame(["col" => "one", "col2" => "two"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["or", "col" => ["=", ["one", "two"]]], $sql, $params);
+    _sqliteQuery::parse_conds(["or", "col" => ["=", ["one", "two"]]], $sql, $params);
     self::assertSame(["col = :col or col = :col2"], $sql);
     self::assertSame(["col" => "one", "col2" => "two"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["col" => ["<>", ["one", "two"]]], $sql, $params);
+    _sqliteQuery::parse_conds(["col" => ["<>", ["one", "two"]]], $sql, $params);
     self::assertSame(["col <> :col and col <> :col2"], $sql);
     self::assertSame(["col" => "one", "col2" => "two"], $params);
 
     $sql = $params = null;
-    query::parse_conds(["or", "col" => ["<>", ["one", "two"]]], $sql, $params);
+    _sqliteQuery::parse_conds(["or", "col" => ["<>", ["one", "two"]]], $sql, $params);
     self::assertSame(["col <> :col or col <> :col2"], $sql);
     self::assertSame(["col" => "one", "col2" => "two"], $params);
   }
 
   function testParseValues(): void {
     $sql = $params = null;
-    query::parse_set_values(null, $sql, $params);
+    _sqliteQuery::parse_set_values(null, $sql, $params);
     self::assertNull($sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_set_values([], $sql, $params);
+    _sqliteQuery::parse_set_values([], $sql, $params);
     self::assertNull($sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_set_values(["col = 'value'"], $sql, $params);
+    _sqliteQuery::parse_set_values(["col = 'value'"], $sql, $params);
     self::assertSame(["col = 'value'"], $sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_set_values([["col = 'value'"]], $sql, $params);
+    _sqliteQuery::parse_set_values([["col = 'value'"]], $sql, $params);
     self::assertSame(["col = 'value'"], $sql);
     self::assertNull($params);
 
     $sql = $params = null;
-    query::parse_set_values(["int" => 42, "string" => "value"], $sql, $params);
+    _sqliteQuery::parse_set_values(["int" => 42, "string" => "value"], $sql, $params);
     self::assertSame(["int = :int", "string = :string"], $sql);
     self::assertSame(["int" => 42, "string" => "value"], $params);
 
     $sql = $params = null;
-    query::parse_set_values(["int" => 42, "string" => "value"], $sql, $params);
+    _sqliteQuery::parse_set_values(["int" => 42, "string" => "value"], $sql, $params);
     self::assertSame(["int = :int", "string = :string"], $sql);
     self::assertSame(["int" => 42, "string" => "value"], $params);
 
     $sql = $params = null;
-    query::parse_set_values([["int" => 42, "string" => "value"], ["int" => 24, "string" => "eulav"]], $sql, $params);
+    _sqliteQuery::parse_set_values([["int" => 42, "string" => "value"], ["int" => 24, "string" => "eulav"]], $sql, $params);
     self::assertSame(["int = :int", "string = :string", "int = :int2", "string = :string2"], $sql);
     self::assertSame(["int" => 42, "string" => "value", "int2" => 24, "string2" => "eulav"], $params);
   }