13 lines
869 B
PHP
13 lines
869 B
PHP
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DQL LIMIT clause is portable on all supported databases. Special attention have been paid to following facts:
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<br \><br \>
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<li \> Only Mysql, Pgsql and Sqlite implement LIMIT / OFFSET clauses natively
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<br \><br \>
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<li \> In Oracle / Mssql / Firebird LIMIT / OFFSET clauses need to be emulated in driver specific way
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<br \><br \>
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<li \> The limit-subquery-algorithm needs to execute to subquery separately in mysql, since mysql doesn't yet support
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LIMIT clause in subqueries<br \><br \>
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<li \> Pgsql needs the order by fields to be preserved in SELECT clause, hence LS-algorithm needs to take this into consideration
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when pgsql driver is used<br \><br \>
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<li \> Oracle only allows < 30 object identifiers (= table/column names/aliases), hence the limit subquery must use as short aliases as possible
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and it must avoid alias collisions with the main query.
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