Extensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 1.11 Playhouse, extensions to Peewee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . hash_functions=True) >>> db.execute_sql('SELECT murmurhash(?)', ('abcdefg',)).fetchone() (4188131059,) 1.11 Playhouse, extensions to Peewee Peewee comes with numerous extension modules which are collected apsw, an advanced sqlite driver • Sqlcipher backend • Postgresql Extensions • MySQL Extensions 1.11. Playhouse, extensions to Peewee 181 peewee Documentation, Release 3.5.0 High-level features •

Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 1.11 SQLite Extensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . peewee Documentation, Release 3.6.0 Add a callback to be executed when the proxy is initialized. 1.11 SQLite Extensions The default SqliteDatabase already includes many SQLite-specific features: • General value is ignored. Example: @db.on_rollback def on_rollback(): logger.info('Rolling back changes') 1.11. SQLite Extensions 175 peewee Documentation, Release 3.6.0 on_update(fn) Register a callback to

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 1.11 Performance Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . appropriate SQL expression: Category.parent == join_query.c.id # Becomes: (t1."parent_id" = "jq"."id") 1.11 Performance Techniques This section outlines some techniques for improving performance when using depending on the size and shape of the data you are querying, one may be more performant than the other. 1.11. Performance Techniques 75 peewee Documentation, Release 2.10.2 Using prefetch peewee supports

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 1.11 Performance Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . appropriate SQL expression: Category.parent == join_query.c.id # Becomes: (t1."parent_id" = "jq"."id") 1.11 Performance Techniques This section outlines some techniques for improving performance when using of indices or other optimizations employed by the database when joining or executing a subquery. 1.11. Performance Techniques 105 peewee Documentation, Release 3.3.0 Peewee provides several APIs for

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 1.11 Performance Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . appropriate SQL expression: Category.parent == join_query.c.id # Becomes: (t1."parent_id" = "jq"."id") 1.11 Performance Techniques This section outlines some techniques for improving performance when using appropriate user. This method is usually faster but will involve a query for each table being selected. 1.11. Performance Techniques 107 peewee Documentation, Release 3.4.0 Using prefetch peewee supports