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Improve CHAR() description.
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doc/FAQ
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doc/FAQ
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Frequently Asked Questions (FAQ) for PostgreSQL
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Last updated: Tue Dec 17 23:56:27 EST 2002
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Last updated: Sun Jan 12 00:16:01 EST 2003
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Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
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@ -834,13 +834,14 @@ BYTEA bytea variable-length byte array (null-byte safe)
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space used is slightly greater than the declared size. However, these
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data types are also subject to compression or being stored out-of-line
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by TOAST, so the space on disk might also be less than expected.
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CHAR(n) is best when storing strings that are usually the same length.
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VARCHAR(n) is best when storing variable-length strings but it limits
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how long a string can be. TEXT is for strings of unlimited length,
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maximum 1 gigabyte. BYTEA is for storing binary data, particularly
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values that include NULL bytes. These types have similar performance
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characteristics.
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maximum 1 gigabyte.
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CHAR(n) is for storing strings that are all the same length. CHAR(n)
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stores trailing spaces, while VARCHAR(n) trims them. BYTEA is for
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storing binary data, particularly values that include NULL bytes.
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These types have similar performance characteristics.
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4.15.1) How do I create a serial/auto-incrementing field?
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