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1. # The query is parsed, i.e., the original query string is transformed to an executable tree representation.2. # External values that are passed on by APIs are bound to variables and the query context. External values can be names of databases, or contribute to a name that will be assembled later on in the query.3. # The query is compiled and evaluated.
→Compilation
Several internal steps are performed when a query is executed (see [[XQuery Optimizations#Introduction|XQuery Optimizations]] for more details):
The [[Transaction_Management|transaction manager]] gathers the names of the databases that will be accessed by a query. If it is not possible to uniquely identify all databases that may be opened by the query, global locking will be applied, and all databases will be locked. Detection can fail if the names of databases depend on external input. It can also fail if a query is too complex to associate character strings with database operations.
