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Implement TODO item:
* Change LIMIT val,val to offset,limit to match MySQL Documentation updates too.
This commit is contained in:
Bruce Momjian
parent
ddfdb1e3f1
commit
1aab783b59
8
doc/TODO
8
doc/TODO
@ -74,10 +74,10 @@ TYPES
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o Allow nulls in arrays
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o Allow arrays to be ORDER'ed
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o fix array handling in ECPG
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BINARY DATA
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lfBINARY DATA
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o -Add non-large-object binary field (already exists -- bytea)
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o -Make binary interface for TOAST columns (base64)
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o Improve vacuum of large objects (/contrib/vacuumlo)
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o Improve vacuum of large objects, like /contrib/vacuumlo
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o Add security checking for large objects
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o Make file in/out interface for TOAST columns, similar to large object
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interface (force out-of-line storage and no compression)
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@ -105,7 +105,7 @@ INDEXES
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* Allow CREATE INDEX zman_index ON test (date_trunc( 'day', zman ) datetime_ops)
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fails index can't store constant parameters
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* Add FILLFACTOR to index creation
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* Order duplicate index entries by tid
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* Order duplicate index entries by tid for faster heap lookups
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* -Re-enable partial indexes
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* -Prevent pg_attribute from having duplicate oids for indexes (Tom)
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* Allow inherited tables to inherit index, UNIQUE constraint, and primary
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@ -124,7 +124,7 @@ INDEXES
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non-consecutive keys or OR clauses, so fewer heap accesses
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* Allow SELECT * FROM tab WHERE int2col = 4 to use int2col index, int8,
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float4, numeric/decimal too [optimizer]
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* Use indexes with CIDR '<<' (contains) operator
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* -Use indexes with CIDR '<<' (contains) operator
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* Allow LIKE indexing optimization for non-ASCII locales
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* Be smarter about insertion of already-ordered data into btree index
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* -Gather more accurate dispersion statistics using indexes (Tom)
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@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/ref/select.sgml,v 1.46 2001/09/14 10:28:09 ishii Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/ref/select.sgml,v 1.47 2001/09/23 03:39:01 momjian Exp $
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Postgres documentation
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-->
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@ -29,7 +29,8 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="PARAMETER">expression</replac
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[ { UNION | INTERSECT | EXCEPT [ ALL ] } <replaceable class="PARAMETER">select</replaceable> ]
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[ ORDER BY <replaceable class="PARAMETER">expression</replaceable> [ ASC | DESC | USING <replaceable class="PARAMETER">operator</replaceable> ] [, ...] ]
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[ FOR UPDATE [ OF <replaceable class="PARAMETER">tablename</replaceable> [, ...] ] ]
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[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } [ { OFFSET | , } <replaceable class="PARAMETER">start</replaceable> ]]
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[ LIMIT [ <replaceable class="PARAMETER">start</replaceable> , ] { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
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[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
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where <replaceable class="PARAMETER">from_item</replaceable> can be:
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@ -613,7 +614,8 @@ SELECT name FROM distributors ORDER BY code;
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<synopsis>
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<replaceable class="PARAMETER">table_query</replaceable> UNION [ ALL ] <replaceable class="PARAMETER">table_query</replaceable>
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[ ORDER BY <replaceable class="PARAMETER">expression</replaceable> [ ASC | DESC | USING <replaceable class="PARAMETER">operator</replaceable> ] [, ...] ]
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[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } [ { OFFSET | , } <replaceable class="PARAMETER">start</replaceable> ]]
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[ LIMIT [ <replaceable class="PARAMETER">start</replaceable> , ] { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
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[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
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</synopsis>
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where
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@ -662,7 +664,8 @@ SELECT name FROM distributors ORDER BY code;
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<synopsis>
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<replaceable class="PARAMETER">table_query</replaceable> INTERSECT [ ALL ] <replaceable class="PARAMETER">table_query</replaceable>
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[ ORDER BY <replaceable class="PARAMETER">expression</replaceable> [ ASC | DESC | USING <replaceable class="PARAMETER">operator</replaceable> ] [, ...] ]
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[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } [ { OFFSET | , } <replaceable class="PARAMETER">start</replaceable> ]]
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[ LIMIT [ <replaceable class="PARAMETER">start</replaceable> , ] { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
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[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
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</synopsis>
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where
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@ -702,7 +705,8 @@ SELECT name FROM distributors ORDER BY code;
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<synopsis>
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<replaceable class="PARAMETER">table_query</replaceable> EXCEPT [ ALL ] <replaceable class="PARAMETER">table_query</replaceable>
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[ ORDER BY <replaceable class="PARAMETER">expression</replaceable> [ ASC | DESC | USING <replaceable class="PARAMETER">operator</replaceable> ] [, ...] ]
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[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } [ { OFFSET | , } <replaceable class="PARAMETER">start</replaceable> ]]
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[ LIMIT [ <replaceable class="PARAMETER">start</replaceable> , ] { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
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[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
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</synopsis>
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where
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@ -738,7 +742,7 @@ SELECT name FROM distributors ORDER BY code;
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</title>
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<para>
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<synopsis>
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LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } [ { OFFSET | , } <replaceable class="PARAMETER">start</replaceable> ]
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LIMIT [ <replaceable class="PARAMETER">start</replaceable> , ] { <replaceable class="PARAMETER">count</replaceable> | ALL }
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OFFSET <replaceable class="PARAMETER">start</replaceable>
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</synopsis>
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@ -761,14 +765,14 @@ SELECT name FROM distributors ORDER BY code;
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constrains the result rows into a unique order. Otherwise you will get
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an unpredictable subset of the query's rows---you may be asking for
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the tenth through twentieth rows, but tenth through twentieth in what
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ordering? You don't know what ordering, unless you specified ORDER BY.
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ordering? You don't know what ordering unless you specify ORDER BY.
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</para>
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<para>
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As of <productname>Postgres</productname> 7.0, the
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query optimizer takes LIMIT into account when generating a query plan,
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so you are very likely to get different plans (yielding different row
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orders) depending on what you give for LIMIT and OFFSET. Thus, using
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orders) depending on what you use for LIMIT and OFFSET. Thus, using
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different LIMIT/OFFSET values to select different subsets of a query
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result <emphasis>will give inconsistent results</emphasis> unless
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you enforce a predictable result ordering with ORDER BY. This is not
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@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/sql.sgml,v 1.21 2001/05/22 16:00:00 petere Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/sql.sgml,v 1.22 2001/09/23 03:39:01 momjian Exp $
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-->
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<chapter id="sql">
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@ -864,7 +864,8 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="PARAMETER">expression</replac
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[ { UNION | INTERSECT | EXCEPT [ ALL ] } <replaceable class="PARAMETER">select</replaceable> ]
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[ ORDER BY <replaceable class="PARAMETER">expression</replaceable> [ ASC | DESC | USING <replaceable class="PARAMETER">operator</replaceable> ] [, ...] ]
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[ FOR UPDATE [ OF <replaceable class="PARAMETER">class_name</replaceable> [, ...] ] ]
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[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } [ { OFFSET | , } <replaceable class="PARAMETER">start</replaceable> ]]
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[ LIMIT [ <replaceable class="PARAMETER">start</replaceable> , ] { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
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[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
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</synopsis>
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</para>
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@ -11,7 +11,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.252 2001/09/20 14:20:27 petere Exp $
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* $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.253 2001/09/23 03:39:01 momjian Exp $
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*
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* HISTORY
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* AUTHOR DATE MAJOR EVENT
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@ -3587,8 +3587,8 @@ OptUseOp: USING all_Op { $$ = $2; }
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;
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select_limit: LIMIT select_limit_value ',' select_offset_value
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{ $$ = makeList2($4, $2); }
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select_limit: LIMIT select_offset_value ',' select_limit_value
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{ $$ = makeList2($2, $4); }
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| LIMIT select_limit_value OFFSET select_offset_value
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{ $$ = makeList2($4, $2); }
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| LIMIT select_limit_value
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