Index[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] scalability, locking and scattering data with partitioning schemas classical order schema movie database (example) searches dynamically defined criteria designing movie database and main query mistakes common in queries redesigning query for tight fit with criteria wrapping SQL in PHP efficiency, descriptions and second normal form (2NF) select distinct queries select operator, filtering conditions selectivity of an index self-joins 2nd performance and 2nd semantic inconsistency sensitivity of operations to volume increases disentangling subqueries insensitivity to linear sensitivity to non-linear sensitivity to sequences call to database for new value not using in order to limit contention server load increase in servers set operators assembling data from several sources getting rid of unwanted data quickly sets nested set model, SQL trees 2nd bottom-up walk top-down walk processing in SQL relational theory and slow database it's not the database particularly slow query slow performance degradation reaching a threshold sudden global sluggishness sudden localized slowness snapshots 2nd solutions (ready-made), problems caused by sorts volume increases and delaying joins to end of query spreading data across many servers SQL art of, governing factors number of tables number of users result set criteria result set size total quantity of data general characteristics of relational and non-relational aspects SQL and databases SQL and the optimizer wrapping in PHP SQL Communication Area (SQLCA) SQL engine cache SQL Server clustered index pivot and unpivot operators recursive with statement star schema querying tables querying through facts and dimensions star transformation emulating statements action-packed first questions to consider when writing mirroring business logic relating load to execution of succinct statistical functions statistics, automated collection of status, partitioning by storage options other than default, introducing complexity with peculiarities in temporary stored procedures 2nd strategy, defining tactics with strings comparing extracting individual characters and returning them on separate rows structural types, databases subqueries correlated or uncorrelated, deciding between sensitivity of operations to data volume increases use in processing massive numbers of rows value of an item on a given date where clauses subtypes defining to deal with varying numbers of attributes succinct statements summary tables, pre-joining vs. Sybase, clustered index syllogisms synchronization of databases after recovery synchronous processing synonyms, comparison to functionally equivalent queries system changes in, causing sudden global slowness complexity of database connections distributed tuning system-generated keys system-generated values not using in order to prevent contention 2nd |