Known limitations

These limits come from ClickHouse or from the design of the package.

Limit	What to do
No transactions. beginTransaction(), transaction() and commit() throw a LogicException.	Use the DatabaseTruncation test trait. See Tests.
No auto-increment. insertGetId() needs the key in the row.	Use HasUuids or HasUlids on a model, or set the key, for example with Str::uuid(). The Eloquent model of the package has $incrementing = false. See Keys.
No foreign keys, unique constraints or spatial indexes.	The schema builder sends nothing for them.
An update or a deletion is a mutation, which ClickHouse runs in the background.	Wait for it with ->settings('mutations_sync', 2), or use a lightweight delete. See Mutation settings.
A mutation uses only the where and prewhere conditions.	The package refuses other clauses. Select the keys first. See Refused clauses.
A computed float keeps all its digits: 4.35 * 100 is 434.99999999999994. A Decimal(10, 2) column stores 434.99, and an Int column cuts the fraction.	Round the float to the scale of the column, or give a numeric string or an int.
ClickHouse 24.8 has no correlated sub-queries. withCount(), withExists() and the other with aggregates of relations fail on 24.8, and so does a whereHas() whose query reads the outer table or has a limit(). On 26.3 and 26.8, withCount() gives null, not 0, for a model without related rows.	Use 26.3 or later, or select the keys first. Write $user->posts_count ?? 0. has() and whereHas() use an IN sub-query otherwise. See Relations.
upsert() and insertOrIgnore() of Laravel's query builder throw.	See Not supported.
JSON paths read a String column, not the native JSON type, and update() cannot set an array element of a path.	Read a JSON column with whereRaw(). Update the whole column. See JSON paths.
time(), fullText(), vectorIndex() and whereFullText() need ClickHouse 26.3 or later. set() and computed() throw.	See Text and vector indexes and Not supported.
At datetime_precision microsecond, created_at and updated_at have a sub-second part, which a DateTime column refuses on ClickHouse 24.8 and 26.3. 26.8 cuts it to the second.	Create the columns with $table->timestamps(6), or set $dateFormat = 'Y-m-d H:i:s' on the model. See Date format.
select(), get() and Parallel read only JSON results.	Read another format with getStatement('CSV')->rawData() of the query builder, or with DB::connection('clickhouse')->selectStatement($sql)->rawData().
A session runs one query at a time. Parallel, insertFiles() and asynchronous requests throw in a session.	See Sessions.
A read-only user, the readonly option of a connection, cannot change a setting. A Decimal then comes as a JSON number, which keeps about 15 significant digits, and NaN and the infinities of a Float come as null.	Use a user that can change settings, such as a profile with readonly = 2. See Static analysis.
The PHPStan extension finds the connection of a migration only when it is a constant: Schema::connection('clickhouse'), or a string in the $connection property of the migration.	Declare SchemaBlueprint as the type of the parameter of the schema callback. See Static analysis.