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prepare() - what happens in the server
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– |
Receive and
parse the SQL statement into internal form
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Get details for
all the selected tables
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Check access
rights for each
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Get details for
all the selected fields
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Check data types
in expressions
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Get details for
all the indices of the tables
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Develop an
optimised query 'access plan' for best execution
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Return a handle
for all this cached information
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n |
This can be an
expensive process - especially the 'access plan'
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n |
Some databases,
like MySQL, don't cache the information but
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have simpler,
and thus faster, plan creation
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