Ein nicht so ernsthafter Blick auf typische Fehler und Probleme mit Hibernate.

1. Todesursache:
Hibernate
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2. CDI 2.0 Expert
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3. Disclaimer:
You can use Hibernate for
high-performance applications
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4. Breaking Things = MORE FUN!
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5. Howtokillaproject • Veeeery bad performance
• Inconsistent results
• Data loss
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6. Bad Performance
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7. AvoidBadPerformance • Use FetchType.LAZY & use case specific projections
• Exclude associations in equals / hashCode / toString
• Use Set instead of List
• Be careful about CascadeType.REMOVE
• Check 2nd Level Cache configuration with Query Cache
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8. Inconsistent Results
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9. AvoidInconsistentResults • Use separate JOIN and JOIN FETCH clauses
• Don‘t forget your caches
• Update both ends of bi-directional associations
• Don‘t use Open Session in View anti-pattern
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10. Data Loss
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11. AvoidDataLoss • Never clear without flush
• Don‘t use CascadeType.REMOVE for Many-to-Many
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