Provided by: postgresql-client-14_14.5-1ubuntu1_amd64 bug

NAME

       COPY - copy data between a file and a table

SYNOPSIS

       COPY table_name [ ( column_name [, ...] ) ]
           FROM { 'filename' | PROGRAM 'command' | STDIN }
           [ [ WITH ] ( option [, ...] ) ]
           [ WHERE condition ]

       COPY { table_name [ ( column_name [, ...] ) ] | ( query ) }
           TO { 'filename' | PROGRAM 'command' | STDOUT }
           [ [ WITH ] ( option [, ...] ) ]

       where option can be one of:

           FORMAT format_name
           FREEZE [ boolean ]
           DELIMITER 'delimiter_character'
           NULL 'null_string'
           HEADER [ boolean ]
           QUOTE 'quote_character'
           ESCAPE 'escape_character'
           FORCE_QUOTE { ( column_name [, ...] ) | * }
           FORCE_NOT_NULL ( column_name [, ...] )
           FORCE_NULL ( column_name [, ...] )
           ENCODING 'encoding_name'

DESCRIPTION

       COPY moves data between PostgreSQL tables and standard file-system files.  COPY TO copies
       the contents of a table to a file, while COPY FROM copies data from a file to a table
       (appending the data to whatever is in the table already).  COPY TO can also copy the
       results of a SELECT query.

       If a column list is specified, COPY TO copies only the data in the specified columns to
       the file. For COPY FROM, each field in the file is inserted, in order, into the specified
       column. Table columns not specified in the COPY FROM column list will receive their
       default values.

       COPY with a file name instructs the PostgreSQL server to directly read from or write to a
       file. The file must be accessible by the PostgreSQL user (the user ID the server runs as)
       and the name must be specified from the viewpoint of the server. When PROGRAM is
       specified, the server executes the given command and reads from the standard output of the
       program, or writes to the standard input of the program. The command must be specified
       from the viewpoint of the server, and be executable by the PostgreSQL user. When STDIN or
       STDOUT is specified, data is transmitted via the connection between the client and the
       server.

       Each backend running COPY will report its progress in the pg_stat_progress_copy view. See
       Section 28.4.6 for details.

PARAMETERS

       table_name
           The name (optionally schema-qualified) of an existing table.

       column_name
           An optional list of columns to be copied. If no column list is specified, all columns
           of the table except generated columns will be copied.

       query
           A SELECT, VALUES, INSERT, UPDATE, or DELETE command whose results are to be copied.
           Note that parentheses are required around the query.

           For INSERT, UPDATE and DELETE queries a RETURNING clause must be provided, and the
           target relation must not have a conditional rule, nor an ALSO rule, nor an INSTEAD
           rule that expands to multiple statements.

       filename
           The path name of the input or output file. An input file name can be an absolute or
           relative path, but an output file name must be an absolute path. Windows users might
           need to use an E'' string and double any backslashes used in the path name.

       PROGRAM
           A command to execute. In COPY FROM, the input is read from standard output of the
           command, and in COPY TO, the output is written to the standard input of the command.

           Note that the command is invoked by the shell, so if you need to pass any arguments to
           shell command that come from an untrusted source, you must be careful to strip or
           escape any special characters that might have a special meaning for the shell. For
           security reasons, it is best to use a fixed command string, or at least avoid passing
           any user input in it.

       STDIN
           Specifies that input comes from the client application.

       STDOUT
           Specifies that output goes to the client application.

       boolean
           Specifies whether the selected option should be turned on or off. You can write TRUE,
           ON, or 1 to enable the option, and FALSE, OFF, or 0 to disable it. The boolean value
           can also be omitted, in which case TRUE is assumed.

       FORMAT
           Selects the data format to be read or written: text, csv (Comma Separated Values), or
           binary. The default is text.

       FREEZE
           Requests copying the data with rows already frozen, just as they would be after
           running the VACUUM FREEZE command. This is intended as a performance option for
           initial data loading. Rows will be frozen only if the table being loaded has been
           created or truncated in the current subtransaction, there are no cursors open and
           there are no older snapshots held by this transaction. It is currently not possible to
           perform a COPY FREEZE on a partitioned table.

           Note that all other sessions will immediately be able to see the data once it has been
           successfully loaded. This violates the normal rules of MVCC visibility and users
           specifying should be aware of the potential problems this might cause.

       DELIMITER
           Specifies the character that separates columns within each row (line) of the file. The
           default is a tab character in text format, a comma in CSV format. This must be a
           single one-byte character. This option is not allowed when using binary format.

       NULL
           Specifies the string that represents a null value. The default is \N (backslash-N) in
           text format, and an unquoted empty string in CSV format. You might prefer an empty
           string even in text format for cases where you don't want to distinguish nulls from
           empty strings. This option is not allowed when using binary format.

               Note
               When using COPY FROM, any data item that matches this string will be stored as a
               null value, so you should make sure that you use the same string as you used with
               COPY TO.

       HEADER
           Specifies that the file contains a header line with the names of each column in the
           file. On output, the first line contains the column names from the table, and on
           input, the first line is ignored. This option is allowed only when using CSV format.

       QUOTE
           Specifies the quoting character to be used when a data value is quoted. The default is
           double-quote. This must be a single one-byte character. This option is allowed only
           when using CSV format.

       ESCAPE
           Specifies the character that should appear before a data character that matches the
           QUOTE value. The default is the same as the QUOTE value (so that the quoting character
           is doubled if it appears in the data). This must be a single one-byte character. This
           option is allowed only when using CSV format.

       FORCE_QUOTE
           Forces quoting to be used for all non-NULL values in each specified column.  NULL
           output is never quoted. If * is specified, non-NULL values will be quoted in all
           columns. This option is allowed only in COPY TO, and only when using CSV format.

       FORCE_NOT_NULL
           Do not match the specified columns' values against the null string. In the default
           case where the null string is empty, this means that empty values will be read as
           zero-length strings rather than nulls, even when they are not quoted. This option is
           allowed only in COPY FROM, and only when using CSV format.

       FORCE_NULL
           Match the specified columns' values against the null string, even if it has been
           quoted, and if a match is found set the value to NULL. In the default case where the
           null string is empty, this converts a quoted empty string into NULL. This option is
           allowed only in COPY FROM, and only when using CSV format.

       ENCODING
           Specifies that the file is encoded in the encoding_name. If this option is omitted,
           the current client encoding is used. See the Notes below for more details.

       WHERE
           The optional WHERE clause has the general form

               WHERE condition

           where condition is any expression that evaluates to a result of type boolean. Any row
           that does not satisfy this condition will not be inserted to the table. A row
           satisfies the condition if it returns true when the actual row values are substituted
           for any variable references.

           Currently, subqueries are not allowed in WHERE expressions, and the evaluation does
           not see any changes made by the COPY itself (this matters when the expression contains
           calls to VOLATILE functions).

OUTPUTS

       On successful completion, a COPY command returns a command tag of the form

           COPY count

       The count is the number of rows copied.

           Note
           psql will print this command tag only if the command was not COPY ... TO STDOUT, or
           the equivalent psql meta-command \copy ... to stdout. This is to prevent confusing the
           command tag with the data that was just printed.

NOTES

       COPY TO can be used only with plain tables, not views, and does not copy rows from child
       tables or child partitions. For example, COPY table TO copies the same rows as SELECT *
       FROM ONLY table. The syntax COPY (SELECT * FROM table) TO ...  can be used to dump all of
       the rows in an inheritance hierarchy, partitioned table, or view.

       COPY FROM can be used with plain, foreign, or partitioned tables or with views that have
       INSTEAD OF INSERT triggers.

       You must have select privilege on the table whose values are read by COPY TO, and insert
       privilege on the table into which values are inserted by COPY FROM. It is sufficient to
       have column privileges on the column(s) listed in the command.

       If row-level security is enabled for the table, the relevant SELECT policies will apply to
       COPY table TO statements. Currently, COPY FROM is not supported for tables with row-level
       security. Use equivalent INSERT statements instead.

       Files named in a COPY command are read or written directly by the server, not by the
       client application. Therefore, they must reside on or be accessible to the database server
       machine, not the client. They must be accessible to and readable or writable by the
       PostgreSQL user (the user ID the server runs as), not the client. Similarly, the command
       specified with PROGRAM is executed directly by the server, not by the client application,
       must be executable by the PostgreSQL user.  COPY naming a file or command is only allowed
       to database superusers or users who are granted one of the roles pg_read_server_files,
       pg_write_server_files, or pg_execute_server_program, since it allows reading or writing
       any file or running a program that the server has privileges to access.

       Do not confuse COPY with the psql instruction \copy.  \copy invokes COPY FROM STDIN or
       COPY TO STDOUT, and then fetches/stores the data in a file accessible to the psql client.
       Thus, file accessibility and access rights depend on the client rather than the server
       when \copy is used.

       It is recommended that the file name used in COPY always be specified as an absolute path.
       This is enforced by the server in the case of COPY TO, but for COPY FROM you do have the
       option of reading from a file specified by a relative path. The path will be interpreted
       relative to the working directory of the server process (normally the cluster's data
       directory), not the client's working directory.

       Executing a command with PROGRAM might be restricted by the operating system's access
       control mechanisms, such as SELinux.

       COPY FROM will invoke any triggers and check constraints on the destination table.
       However, it will not invoke rules.

       For identity columns, the COPY FROM command will always write the column values provided
       in the input data, like the INSERT option OVERRIDING SYSTEM VALUE.

       COPY input and output is affected by DateStyle. To ensure portability to other PostgreSQL
       installations that might use non-default DateStyle settings, DateStyle should be set to
       ISO before using COPY TO. It is also a good idea to avoid dumping data with IntervalStyle
       set to sql_standard, because negative interval values might be misinterpreted by a server
       that has a different setting for IntervalStyle.

       Input data is interpreted according to ENCODING option or the current client encoding, and
       output data is encoded in ENCODING or the current client encoding, even if the data does
       not pass through the client but is read from or written to a file directly by the server.

       COPY stops operation at the first error. This should not lead to problems in the event of
       a COPY TO, but the target table will already have received earlier rows in a COPY FROM.
       These rows will not be visible or accessible, but they still occupy disk space. This might
       amount to a considerable amount of wasted disk space if the failure happened well into a
       large copy operation. You might wish to invoke VACUUM to recover the wasted space.

       FORCE_NULL and FORCE_NOT_NULL can be used simultaneously on the same column. This results
       in converting quoted null strings to null values and unquoted null strings to empty
       strings.

FILE FORMATS

   Text Format
       When the text format is used, the data read or written is a text file with one line per
       table row. Columns in a row are separated by the delimiter character. The column values
       themselves are strings generated by the output function, or acceptable to the input
       function, of each attribute's data type. The specified null string is used in place of
       columns that are null.  COPY FROM will raise an error if any line of the input file
       contains more or fewer columns than are expected.

       End of data can be represented by a single line containing just backslash-period (\.). An
       end-of-data marker is not necessary when reading from a file, since the end of file serves
       perfectly well; it is needed only when copying data to or from client applications using
       pre-3.0 client protocol.

       Backslash characters (\) can be used in the COPY data to quote data characters that might
       otherwise be taken as row or column delimiters. In particular, the following characters
       must be preceded by a backslash if they appear as part of a column value: backslash
       itself, newline, carriage return, and the current delimiter character.

       The specified null string is sent by COPY TO without adding any backslashes; conversely,
       COPY FROM matches the input against the null string before removing backslashes.
       Therefore, a null string such as \N cannot be confused with the actual data value \N
       (which would be represented as \\N).

       The following special backslash sequences are recognized by COPY FROM:

       ┌─────────┬────────────────────────────────┐
       │SequenceRepresents                     │
       ├─────────┼────────────────────────────────┤
       │\b       │ Backspace (ASCII 8)            │
       ├─────────┼────────────────────────────────┤
       │\f       │ Form feed (ASCII 12)           │
       ├─────────┼────────────────────────────────┤
       │\n       │ Newline (ASCII 10)             │
       ├─────────┼────────────────────────────────┤
       │\r       │ Carriage return (ASCII 13)     │
       ├─────────┼────────────────────────────────┤
       │\t       │ Tab (ASCII 9)                  │
       ├─────────┼────────────────────────────────┤
       │\v       │ Vertical tab (ASCII 11)        │
       ├─────────┼────────────────────────────────┤
       │\digits  │ Backslash followed by one to   │
       │         │ three octal digits specifies   │
       │         │        the byte with that      │
       │         │ numeric code                   │
       ├─────────┼────────────────────────────────┤
       │\xdigits │ Backslash x followed by one or │
       │         │ two hex digits specifies       │
       │         │        the byte with that      │
       │         │ numeric code                   │
       └─────────┴────────────────────────────────┘
       Presently, COPY TO will never emit an octal or hex-digits backslash sequence, but it does
       use the other sequences listed above for those control characters.

       Any other backslashed character that is not mentioned in the above table will be taken to
       represent itself. However, beware of adding backslashes unnecessarily, since that might
       accidentally produce a string matching the end-of-data marker (\.) or the null string (\N
       by default). These strings will be recognized before any other backslash processing is
       done.

       It is strongly recommended that applications generating COPY data convert data newlines
       and carriage returns to the \n and \r sequences respectively. At present it is possible to
       represent a data carriage return by a backslash and carriage return, and to represent a
       data newline by a backslash and newline. However, these representations might not be
       accepted in future releases. They are also highly vulnerable to corruption if the COPY
       file is transferred across different machines (for example, from Unix to Windows or vice
       versa).

       All backslash sequences are interpreted after encoding conversion. The bytes specified
       with the octal and hex-digit backslash sequences must form valid characters in the
       database encoding.

       COPY TO will terminate each row with a Unix-style newline (“\n”). Servers running on
       Microsoft Windows instead output carriage return/newline (“\r\n”), but only for COPY to a
       server file; for consistency across platforms, COPY TO STDOUT always sends “\n” regardless
       of server platform.  COPY FROM can handle lines ending with newlines, carriage returns, or
       carriage return/newlines. To reduce the risk of error due to un-backslashed newlines or
       carriage returns that were meant as data, COPY FROM will complain if the line endings in
       the input are not all alike.

   CSV Format
       This format option is used for importing and exporting the Comma Separated Value (CSV)
       file format used by many other programs, such as spreadsheets. Instead of the escaping
       rules used by PostgreSQL's standard text format, it produces and recognizes the common CSV
       escaping mechanism.

       The values in each record are separated by the DELIMITER character. If the value contains
       the delimiter character, the QUOTE character, the NULL string, a carriage return, or line
       feed character, then the whole value is prefixed and suffixed by the QUOTE character, and
       any occurrence within the value of a QUOTE character or the ESCAPE character is preceded
       by the escape character. You can also use FORCE_QUOTE to force quotes when outputting
       non-NULL values in specific columns.

       The CSV format has no standard way to distinguish a NULL value from an empty string.
       PostgreSQL's COPY handles this by quoting. A NULL is output as the NULL parameter string
       and is not quoted, while a non-NULL value matching the NULL parameter string is quoted.
       For example, with the default settings, a NULL is written as an unquoted empty string,
       while an empty string data value is written with double quotes (""). Reading values
       follows similar rules. You can use FORCE_NOT_NULL to prevent NULL input comparisons for
       specific columns. You can also use FORCE_NULL to convert quoted null string data values to
       NULL.

       Because backslash is not a special character in the CSV format, \., the end-of-data
       marker, could also appear as a data value. To avoid any misinterpretation, a \.  data
       value appearing as a lone entry on a line is automatically quoted on output, and on input,
       if quoted, is not interpreted as the end-of-data marker. If you are loading a file created
       by another application that has a single unquoted column and might have a value of \., you
       might need to quote that value in the input file.

           Note
           In CSV format, all characters are significant. A quoted value surrounded by white
           space, or any characters other than DELIMITER, will include those characters. This can
           cause errors if you import data from a system that pads CSV lines with white space out
           to some fixed width. If such a situation arises you might need to preprocess the CSV
           file to remove the trailing white space, before importing the data into PostgreSQL.

           Note
           CSV format will both recognize and produce CSV files with quoted values containing
           embedded carriage returns and line feeds. Thus the files are not strictly one line per
           table row like text-format files.

           Note
           Many programs produce strange and occasionally perverse CSV files, so the file format
           is more a convention than a standard. Thus you might encounter some files that cannot
           be imported using this mechanism, and COPY might produce files that other programs
           cannot process.

   Binary Format
       The binary format option causes all data to be stored/read as binary format rather than as
       text. It is somewhat faster than the text and CSV formats, but a binary-format file is
       less portable across machine architectures and PostgreSQL versions. Also, the binary
       format is very data type specific; for example it will not work to output binary data from
       a smallint column and read it into an integer column, even though that would work fine in
       text format.

       The binary file format consists of a file header, zero or more tuples containing the row
       data, and a file trailer. Headers and data are in network byte order.

           Note
           PostgreSQL releases before 7.4 used a different binary file format.

       File Header
           The file header consists of 15 bytes of fixed fields, followed by a variable-length
           header extension area. The fixed fields are:

           Signature
               11-byte sequence PGCOPY\n\377\r\n\0 — note that the zero byte is a required part
               of the signature. (The signature is designed to allow easy identification of files
               that have been munged by a non-8-bit-clean transfer. This signature will be
               changed by end-of-line-translation filters, dropped zero bytes, dropped high bits,
               or parity changes.)

           Flags field
               32-bit integer bit mask to denote important aspects of the file format. Bits are
               numbered from 0 (LSB) to 31 (MSB). Note that this field is stored in network byte
               order (most significant byte first), as are all the integer fields used in the
               file format. Bits 16–31 are reserved to denote critical file format issues; a
               reader should abort if it finds an unexpected bit set in this range. Bits 0–15 are
               reserved to signal backwards-compatible format issues; a reader should simply
               ignore any unexpected bits set in this range. Currently only one flag bit is
               defined, and the rest must be zero:

               Bit 16
                   If 1, OIDs are included in the data; if 0, not. Oid system columns are not
                   supported in PostgreSQL anymore, but the format still contains the indicator.

           Header extension area length
               32-bit integer, length in bytes of remainder of header, not including self.
               Currently, this is zero, and the first tuple follows immediately. Future changes
               to the format might allow additional data to be present in the header. A reader
               should silently skip over any header extension data it does not know what to do
               with.

           The header extension area is envisioned to contain a sequence of self-identifying
           chunks. The flags field is not intended to tell readers what is in the extension area.
           Specific design of header extension contents is left for a later release.

           This design allows for both backwards-compatible header additions (add header
           extension chunks, or set low-order flag bits) and non-backwards-compatible changes
           (set high-order flag bits to signal such changes, and add supporting data to the
           extension area if needed).

       Tuples
           Each tuple begins with a 16-bit integer count of the number of fields in the tuple.
           (Presently, all tuples in a table will have the same count, but that might not always
           be true.) Then, repeated for each field in the tuple, there is a 32-bit length word
           followed by that many bytes of field data. (The length word does not include itself,
           and can be zero.) As a special case, -1 indicates a NULL field value. No value bytes
           follow in the NULL case.

           There is no alignment padding or any other extra data between fields.

           Presently, all data values in a binary-format file are assumed to be in binary format
           (format code one). It is anticipated that a future extension might add a header field
           that allows per-column format codes to be specified.

           To determine the appropriate binary format for the actual tuple data you should
           consult the PostgreSQL source, in particular the *send and *recv functions for each
           column's data type (typically these functions are found in the src/backend/utils/adt/
           directory of the source distribution).

           If OIDs are included in the file, the OID field immediately follows the field-count
           word. It is a normal field except that it's not included in the field-count. Note that
           oid system columns are not supported in current versions of PostgreSQL.

       File Trailer
           The file trailer consists of a 16-bit integer word containing -1. This is easily
           distinguished from a tuple's field-count word.

           A reader should report an error if a field-count word is neither -1 nor the expected
           number of columns. This provides an extra check against somehow getting out of sync
           with the data.

EXAMPLES

       The following example copies a table to the client using the vertical bar (|) as the field
       delimiter:

           COPY country TO STDOUT (DELIMITER '|');

       To copy data from a file into the country table:

           COPY country FROM '/usr1/proj/bray/sql/country_data';

       To copy into a file just the countries whose names start with 'A':

           COPY (SELECT * FROM country WHERE country_name LIKE 'A%') TO '/usr1/proj/bray/sql/a_list_countries.copy';

       To copy into a compressed file, you can pipe the output through an external compression
       program:

           COPY country TO PROGRAM 'gzip > /usr1/proj/bray/sql/country_data.gz';

       Here is a sample of data suitable for copying into a table from STDIN:

           AF      AFGHANISTAN
           AL      ALBANIA
           DZ      ALGERIA
           ZM      ZAMBIA
           ZW      ZIMBABWE

       Note that the white space on each line is actually a tab character.

       The following is the same data, output in binary format. The data is shown after filtering
       through the Unix utility od -c. The table has three columns; the first has type char(2),
       the second has type text, and the third has type integer. All the rows have a null value
       in the third column.

           0000000   P   G   C   O   P   Y  \n 377  \r  \n  \0  \0  \0  \0  \0  \0
           0000020  \0  \0  \0  \0 003  \0  \0  \0 002   A   F  \0  \0  \0 013   A
           0000040   F   G   H   A   N   I   S   T   A   N 377 377 377 377  \0 003
           0000060  \0  \0  \0 002   A   L  \0  \0  \0 007   A   L   B   A   N   I
           0000100   A 377 377 377 377  \0 003  \0  \0  \0 002   D   Z  \0  \0  \0
           0000120 007   A   L   G   E   R   I   A 377 377 377 377  \0 003  \0  \0
           0000140  \0 002   Z   M  \0  \0  \0 006   Z   A   M   B   I   A 377 377
           0000160 377 377  \0 003  \0  \0  \0 002   Z   W  \0  \0  \0  \b   Z   I
           0000200   M   B   A   B   W   E 377 377 377 377 377 377

COMPATIBILITY

       There is no COPY statement in the SQL standard.

       The following syntax was used before PostgreSQL version 9.0 and is still supported:

           COPY table_name [ ( column_name [, ...] ) ]
               FROM { 'filename' | STDIN }
               [ [ WITH ]
                     [ BINARY ]
                     [ DELIMITER [ AS ] 'delimiter_character' ]
                     [ NULL [ AS ] 'null_string' ]
                     [ CSV [ HEADER ]
                           [ QUOTE [ AS ] 'quote_character' ]
                           [ ESCAPE [ AS ] 'escape_character' ]
                           [ FORCE NOT NULL column_name [, ...] ] ] ]

           COPY { table_name [ ( column_name [, ...] ) ] | ( query ) }
               TO { 'filename' | STDOUT }
               [ [ WITH ]
                     [ BINARY ]
                     [ DELIMITER [ AS ] 'delimiter_character' ]
                     [ NULL [ AS ] 'null_string' ]
                     [ CSV [ HEADER ]
                           [ QUOTE [ AS ] 'quote_character' ]
                           [ ESCAPE [ AS ] 'escape_character' ]
                           [ FORCE QUOTE { column_name [, ...] | * } ] ] ]

       Note that in this syntax, BINARY and CSV are treated as independent keywords, not as
       arguments of a FORMAT option.

       The following syntax was used before PostgreSQL version 7.3 and is still supported:

           COPY [ BINARY ] table_name
               FROM { 'filename' | STDIN }
               [ [USING] DELIMITERS 'delimiter_character' ]
               [ WITH NULL AS 'null_string' ]

           COPY [ BINARY ] table_name
               TO { 'filename' | STDOUT }
               [ [USING] DELIMITERS 'delimiter_character' ]
               [ WITH NULL AS 'null_string' ]

SEE ALSO

       Section 28.4.6