SQL Anywhere uses schema, row, table, and position locks as necessary to ensure the level of consistency that you require. You do not need to explicitly request the use of a particular lock. Instead, you control the level of consistency that is maintained by choosing the isolation level that best fits your requirements. Knowledge of the types of locks will guide you in choosing isolation levels and understanding the impact of each level on performance. Keep in mind that any one transaction cannot block itself by acquiring locks; a locking conflict can only occur between two (or more) transactions.
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