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1 | 1 | <!-- |
2 | | -$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.94 2002/07/1603:30:26 momjian Exp $ |
| 2 | +$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.95 2002/07/1604:45:59 momjian Exp $ |
3 | 3 | --> |
4 | 4 |
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5 | 5 | <chapter id="datatype"> |
@@ -843,19 +843,20 @@ CREATE TABLE <replaceable class="parameter">tablename</replaceable> (<replaceabl |
843 | 843 | </para> |
844 | 844 |
|
845 | 845 | <para> |
846 | | - The storage requirement for data of these types is 4 bytes plus |
847 | | - the actual string, and in case of <type>character</type> plus the |
848 | | - padding. Long strings will be compressed by the system |
849 | | - automatically, so the physical requirement on disk may be less. |
850 | | - In any case, the longest possible character string |
851 | | - that can be stored is about 1 GB. (The maximum value that will be |
852 | | - allowed for <replaceable>n</> in the data type declaration is |
853 | | - less than that. It wouldn't be very useful to change |
854 | | - this because with multibyte character encodings the number of |
855 | | - characters and bytes can be quite different anyway. If you desire |
856 | | - to store long strings with no specific upper limit, use <type>text</type> |
857 | | - or <type>character varying</type> without a length specifier, |
858 | | - rather than making up an arbitrary length limit.) |
| 846 | + The storage requirement for data of these types is 4 bytes plus the |
| 847 | + actual string, and in case of <type>character</type> plus the |
| 848 | + padding. Long strings are compressed by the system automatically, so |
| 849 | + the physical requirement on disk may be less. Long values are also |
| 850 | + stored in background tables so they don't interfere with rapid |
| 851 | + access to the shorter column values. In any case, the longest |
| 852 | + possible character string that can be stored is about 1 GB. (The |
| 853 | + maximum value that will be allowed for <replaceable>n</> in the data |
| 854 | + type declaration is less than that. It wouldn't be very useful to |
| 855 | + change this because with multibyte character encodings the number of |
| 856 | + characters and bytes can be quite different anyway. If you desire to |
| 857 | + store long strings with no specific upper limit, use |
| 858 | + <type>text</type> or <type>character varying</type> without a length |
| 859 | + specifier, rather than making up an arbitrary length limit.) |
859 | 860 | </para> |
860 | 861 |
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861 | 862 | <tip> |
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