1ALTER SEQUENCE(7)        PostgreSQL 11.6 Documentation       ALTER SEQUENCE(7)
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NAME

6       ALTER_SEQUENCE - change the definition of a sequence generator
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SYNOPSIS

9       ALTER SEQUENCE [ IF EXISTS ] name
10           [ AS data_type ]
11           [ INCREMENT [ BY ] increment ]
12           [ MINVALUE minvalue | NO MINVALUE ] [ MAXVALUE maxvalue | NO MAXVALUE ]
13           [ START [ WITH ] start ]
14           [ RESTART [ [ WITH ] restart ] ]
15           [ CACHE cache ] [ [ NO ] CYCLE ]
16           [ OWNED BY { table_name.column_name | NONE } ]
17       ALTER SEQUENCE [ IF EXISTS ] name OWNER TO { new_owner | CURRENT_USER | SESSION_USER }
18       ALTER SEQUENCE [ IF EXISTS ] name RENAME TO new_name
19       ALTER SEQUENCE [ IF EXISTS ] name SET SCHEMA new_schema
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DESCRIPTION

22       ALTER SEQUENCE changes the parameters of an existing sequence
23       generator. Any parameters not specifically set in the ALTER SEQUENCE
24       command retain their prior settings.
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26       You must own the sequence to use ALTER SEQUENCE. To change a sequence's
27       schema, you must also have CREATE privilege on the new schema. To alter
28       the owner, you must also be a direct or indirect member of the new
29       owning role, and that role must have CREATE privilege on the sequence's
30       schema. (These restrictions enforce that altering the owner doesn't do
31       anything you couldn't do by dropping and recreating the sequence.
32       However, a superuser can alter ownership of any sequence anyway.)
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PARAMETERS

35       name
36           The name (optionally schema-qualified) of a sequence to be altered.
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38       IF EXISTS
39           Do not throw an error if the sequence does not exist. A notice is
40           issued in this case.
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42       data_type
43           The optional clause AS data_type changes the data type of the
44           sequence. Valid types are smallint, integer, and bigint.
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46           Changing the data type automatically changes the minimum and
47           maximum values of the sequence if and only if the previous minimum
48           and maximum values were the minimum or maximum value of the old
49           data type (in other words, if the sequence had been created using
50           NO MINVALUE or NO MAXVALUE, implicitly or explicitly). Otherwise,
51           the minimum and maximum values are preserved, unless new values are
52           given as part of the same command. If the minimum and maximum
53           values do not fit into the new data type, an error will be
54           generated.
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56       increment
57           The clause INCREMENT BY increment is optional. A positive value
58           will make an ascending sequence, a negative one a descending
59           sequence. If unspecified, the old increment value will be
60           maintained.
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62       minvalue
63       NO MINVALUE
64           The optional clause MINVALUE minvalue determines the minimum value
65           a sequence can generate. If NO MINVALUE is specified, the defaults
66           of 1 and the minimum value of the data type for ascending and
67           descending sequences, respectively, will be used. If neither option
68           is specified, the current minimum value will be maintained.
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70       maxvalue
71       NO MAXVALUE
72           The optional clause MAXVALUE maxvalue determines the maximum value
73           for the sequence. If NO MAXVALUE is specified, the defaults of the
74           maximum value of the data type and -1 for ascending and descending
75           sequences, respectively, will be used. If neither option is
76           specified, the current maximum value will be maintained.
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78       start
79           The optional clause START WITH start changes the recorded start
80           value of the sequence. This has no effect on the current sequence
81           value; it simply sets the value that future ALTER SEQUENCE RESTART
82           commands will use.
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84       restart
85           The optional clause RESTART [ WITH restart ] changes the current
86           value of the sequence. This is similar to calling the setval
87           function with is_called = false: the specified value will be
88           returned by the next call of nextval. Writing RESTART with no
89           restart value is equivalent to supplying the start value that was
90           recorded by CREATE SEQUENCE or last set by ALTER SEQUENCE START
91           WITH.
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93           In contrast to a setval call, a RESTART operation on a sequence is
94           transactional and blocks concurrent transactions from obtaining
95           numbers from the same sequence. If that's not the desired mode of
96           operation, setval should be used.
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98       cache
99           The clause CACHE cache enables sequence numbers to be preallocated
100           and stored in memory for faster access. The minimum value is 1
101           (only one value can be generated at a time, i.e., no cache). If
102           unspecified, the old cache value will be maintained.
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104       CYCLE
105           The optional CYCLE key word can be used to enable the sequence to
106           wrap around when the maxvalue or minvalue has been reached by an
107           ascending or descending sequence respectively. If the limit is
108           reached, the next number generated will be the minvalue or
109           maxvalue, respectively.
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111       NO CYCLE
112           If the optional NO CYCLE key word is specified, any calls to
113           nextval after the sequence has reached its maximum value will
114           return an error. If neither CYCLE or NO CYCLE are specified, the
115           old cycle behavior will be maintained.
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117       OWNED BY table_name.column_name
118       OWNED BY NONE
119           The OWNED BY option causes the sequence to be associated with a
120           specific table column, such that if that column (or its whole
121           table) is dropped, the sequence will be automatically dropped as
122           well. If specified, this association replaces any previously
123           specified association for the sequence. The specified table must
124           have the same owner and be in the same schema as the sequence.
125           Specifying OWNED BY NONE removes any existing association, making
126           the sequence “free-standing”.
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128       new_owner
129           The user name of the new owner of the sequence.
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131       new_name
132           The new name for the sequence.
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134       new_schema
135           The new schema for the sequence.
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NOTES

138       ALTER SEQUENCE will not immediately affect nextval results in backends,
139       other than the current one, that have preallocated (cached) sequence
140       values. They will use up all cached values prior to noticing the
141       changed sequence generation parameters. The current backend will be
142       affected immediately.
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144       ALTER SEQUENCE does not affect the currval status for the sequence.
145       (Before PostgreSQL 8.3, it sometimes did.)
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147       ALTER SEQUENCE blocks concurrent nextval, currval, lastval, and setval
148       calls.
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150       For historical reasons, ALTER TABLE can be used with sequences too; but
151       the only variants of ALTER TABLE that are allowed with sequences are
152       equivalent to the forms shown above.
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EXAMPLES

155       Restart a sequence called serial, at 105:
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157           ALTER SEQUENCE serial RESTART WITH 105;
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COMPATIBILITY

160       ALTER SEQUENCE conforms to the SQL standard, except for the AS, START
161       WITH, OWNED BY, OWNER TO, RENAME TO, and SET SCHEMA clauses, which are
162       PostgreSQL extensions.
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SEE ALSO

165       CREATE SEQUENCE (CREATE_SEQUENCE(7)), DROP SEQUENCE (DROP_SEQUENCE(7))
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169PostgreSQL 11.6                      2019                    ALTER SEQUENCE(7)
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