diff --git a/core/includes/schema.inc b/core/includes/schema.inc
index 978ec2307af5..0129d19334a7 100644
--- a/core/includes/schema.inc
+++ b/core/includes/schema.inc
@@ -5,6 +5,8 @@
  * Schema API handling functions.
  */
 
+use Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema;
+
 /**
  * @addtogroup schemaapi
  * @{
@@ -215,21 +217,15 @@ function _drupal_schema_initialize(&$schema, $module, $remove_descriptions = TRU
  *
  * @return mixed
  *   The converted value.
+ *
+ * @deprecated in drupal:8.8.0 and will be removed from drupal:9.0.0. Use
+ *   \Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema::castValue() instead.
+ *
+ * @see https://www.drupal.org/node/3051983
  */
 function drupal_schema_get_field_value(array $info, $value) {
-  // Preserve legal NULL values.
-  if (isset($value) || !empty($info['not null'])) {
-    if ($info['type'] == 'int' || $info['type'] == 'serial') {
-      $value = (int) $value;
-    }
-    elseif ($info['type'] == 'float') {
-      $value = (float) $value;
-    }
-    elseif (!is_array($value)) {
-      $value = (string) $value;
-    }
-  }
-  return $value;
+  @trigger_error('drupal_schema_get_field_value() is deprecated in drupal:8.8.0. It will be removed from drupal:9.0.0. Use \Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema::castValue($info, $value) instead. See https://www.drupal.org/node/3051983', E_USER_DEPRECATED);
+  return SqlContentEntityStorageSchema::castValue($info, $value);
 }
 
 /**
diff --git a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
index edf338c9ee09..77edfc117e17 100644
--- a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
+++ b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
@@ -1097,7 +1097,7 @@ class SqlContentEntityStorage extends ContentEntityStorageBase implements SqlEnt
         // Do not set serial fields if we do not have a value. This supports all
         // SQL database drivers.
         // @see https://www.drupal.org/node/2279395
-        $value = drupal_schema_get_field_value($definition->getSchema()['columns'][$column_name], $value);
+        $value = SqlContentEntityStorageSchema::castValue($definition->getSchema()['columns'][$column_name], $value);
         if (!(empty($value) && $this->isColumnSerial($table_name, $schema_name))) {
           $record->$schema_name = $value;
         }
@@ -1398,7 +1398,7 @@ class SqlContentEntityStorage extends ContentEntityStorageBase implements SqlEnt
             if (!empty($attributes['serialize'])) {
               $value = serialize($value);
             }
-            $record[$column_name] = drupal_schema_get_field_value($attributes, $value);
+            $record[$column_name] = SqlContentEntityStorageSchema::castValue($attributes, $value);
           }
           $query->values($record);
           if ($this->entityType->isRevisionable()) {
diff --git a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
index b2d1d291671d..90d05e2438f0 100644
--- a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
+++ b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
@@ -2099,7 +2099,7 @@ class SqlContentEntityStorageSchema implements DynamicallyFieldableEntityStorage
 
       // Use the initial value of the field storage, if available.
       if ($initial_value && isset($initial_value[$field_column_name])) {
-        $schema['fields'][$schema_field_name]['initial'] = drupal_schema_get_field_value($column_schema, $initial_value[$field_column_name]);
+        $schema['fields'][$schema_field_name]['initial'] = SqlContentEntityStorageSchema::castValue($column_schema, $initial_value[$field_column_name]);
       }
       if (!empty($initial_value_from_field)) {
         $schema['fields'][$schema_field_name]['initial_from_field'] = $initial_value_from_field[$field_column_name];
@@ -2506,4 +2506,40 @@ class SqlContentEntityStorageSchema implements DynamicallyFieldableEntityStorage
     $schema_handler->addUniqueKey($table, $name, $specifier);
   }
 
+  /**
+   * Typecasts values to proper datatypes.
+   *
+   * MySQL PDO silently casts, e.g. FALSE and '' to 0, when inserting the value
+   * into an integer column, but PostgreSQL PDO does not. Use the schema
+   * information to correctly typecast the value.
+   *
+   * @param array $info
+   *   An array describing the schema field info. See hook_schema() and
+   *   https://www.drupal.org/node/146843 for details.
+   * @param mixed $value
+   *   The value to be converted.
+   *
+   * @return mixed
+   *   The converted value.
+   *
+   * @internal
+   *
+   * @see hook_schema()
+   * @see https://www.drupal.org/node/146843
+   */
+  public static function castValue(array $info, $value) {
+    // Preserve legal NULL values.
+    if (isset($value) || !empty($info['not null'])) {
+      if ($info['type'] === 'int' || $info['type'] === 'serial') {
+        return (int) $value;
+      }
+      elseif ($info['type'] === 'float') {
+        return (float) $value;
+      }
+      return (string) $value;
+    }
+
+    return $value;
+  }
+
 }
diff --git a/core/tests/Drupal/KernelTests/Core/Database/SchemaLegacyTest.php b/core/tests/Drupal/KernelTests/Core/Database/SchemaLegacyTest.php
new file mode 100644
index 000000000000..35fa7f1aa644
--- /dev/null
+++ b/core/tests/Drupal/KernelTests/Core/Database/SchemaLegacyTest.php
@@ -0,0 +1,26 @@
+<?php
+
+namespace Drupal\KernelTests\Core\Database;
+
+use Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Deprecation tests cases for the schema API.
+ *
+ * @group legacy
+ */
+class SchemaLegacyTest extends KernelTestBase {
+
+  /**
+   * Tests deprecation of the drupal_schema_get_field_value() function.
+   *
+   * @expectedDeprecation drupal_schema_get_field_value() is deprecated in drupal:8.8.0. It will be removed from drupal:9.0.0. Use \Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema::castValue($info, $value) instead. See https://www.drupal.org/node/3051983
+   */
+  public function testSchemaGetFieldValue() {
+    $info = ['type' => 'int'];
+    $value = 1.1;
+    $this->assertEquals(SqlContentEntityStorageSchema::castValue($info, $value), drupal_schema_get_field_value($info, $value));
+  }
+
+}
diff --git a/core/tests/Drupal/Tests/Core/Entity/Sql/SqlContentEntityStorageSchemaTest.php b/core/tests/Drupal/Tests/Core/Entity/Sql/SqlContentEntityStorageSchemaTest.php
index ad30bcae795f..397e1af52009 100644
--- a/core/tests/Drupal/Tests/Core/Entity/Sql/SqlContentEntityStorageSchemaTest.php
+++ b/core/tests/Drupal/Tests/Core/Entity/Sql/SqlContentEntityStorageSchemaTest.php
@@ -8,6 +8,7 @@ use Drupal\Core\Entity\EntityFieldManager;
 use Drupal\Core\Entity\EntityLastInstalledSchemaRepositoryInterface;
 use Drupal\Core\Entity\EntityTypeManager;
 use Drupal\Core\Entity\Sql\DefaultTableMapping;
+use Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema;
 use Drupal\Tests\UnitTestCase;
 
 /**
@@ -1562,4 +1563,121 @@ class SqlContentEntityStorageSchemaTest extends UnitTestCase {
     );
   }
 
+  /**
+   * Tests various value casts depending on column schema.
+   *
+   * @param mixed $expected
+   *   The expected value.
+   * @param mixed $value
+   *   The tested value.
+   * @param array $schema
+   *   The schema for the table column.
+   *
+   * @dataProvider providerSchemaCastValue
+   * @covers ::castValue
+   */
+  public function testCastValue($expected, $value, array $schema) {
+    $this->assertSame($expected, SqlContentEntityStorageSchema::castValue($schema, $value));
+  }
+
+  /**
+   * Provides data for testCastValue().
+   */
+  public function providerSchemaCastValue() {
+    $cases = [];
+    // Tests NULL values.
+    $cases[] = [
+      NULL,
+      NULL,
+      [
+        'not null' => FALSE,
+      ],
+    ];
+    $cases[] = [
+      0,
+      NULL,
+      [
+        'not null' => TRUE,
+        'type' => 'int',
+      ],
+    ];
+    $cases[] = [
+      0,
+      NULL,
+      [
+        'not null' => TRUE,
+        'type' => 'serial',
+      ],
+    ];
+    $cases[] = [
+      0.0,
+      NULL,
+      [
+        'not null' => TRUE,
+        'type' => 'float',
+      ],
+    ];
+    $cases[] = [
+      '',
+      NULL,
+      [
+        'not null' => TRUE,
+        'type' => 'varchar',
+      ],
+    ];
+    // Tests cast to int and serial.
+    $cases[] = [
+      1,
+      '1.001',
+      [
+        'type' => 'int',
+      ],
+    ];
+    $cases[] = [
+      2,
+      2.6,
+      [
+        'type' => 'int',
+      ],
+    ];
+    $cases[] = [
+      3,
+      '3.6',
+      [
+        'type' => 'serial',
+      ],
+    ];
+    // Tests float.
+    $cases[] = [
+      1.001,
+      '1.001',
+      [
+        'type' => 'float',
+      ],
+    ];
+    $cases[] = [
+      2.6,
+      2.6,
+      [
+        'type' => 'float',
+      ],
+    ];
+    // Tests other column types casts to string.
+    $cases[] = [
+      '1',
+      1,
+      [
+        'type' => 'varchar',
+      ],
+    ];
+    $cases[] = [
+      '2',
+      '2',
+      [
+        'type' => 'varchar',
+      ],
+    ];
+    return $cases;
+  }
+
 }