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COPY(7)			PostgreSQL 9.2.24 Documentation		       COPY(7)



NAME
       COPY - copy data between a file and a table

SYNOPSIS
       COPY table_name [ ( column_name [, ...] ) ]
	   FROM { 'filename' | STDIN }
	   [ [ WITH ] ( option [, ...] ) ]

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

       where option can be one of:

	   FORMAT format_name
	   OIDS [ boolean ]
	   DELIMITER 'delimiter_character'
	   NULL 'null_string'
	   HEADER [ boolean ]
	   QUOTE 'quote_character'
	   ESCAPE 'escape_character'
	   FORCE_QUOTE { ( column_name [, ...] ) | * }
	   FORCE_NOT_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 list of columns is specified, COPY will only copy the data in the
       specified columns to or from the file. If there are any columns in the
       table that are not in the column list, COPY FROM will insert the
       default values for those columns.

       COPY with a file name instructs the PostgreSQL server to directly read
       from or write to a file. The file must be accessible to the server and
       the name must be specified from the viewpoint of the server. When STDIN
       or STDOUT is specified, data is transmitted via the connection between
       the client and the server.

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 will be copied.

       query
	   A SELECT(7) or VALUES(7) command whose results are to be copied.
	   Note that parentheses are required around the query.

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

       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.

       OIDS
	   Specifies copying the OID for each row. (An error is raised if OIDS
	   is specified for a table that does not have OIDs, or in the case of
	   copying a query.)

       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.

       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.

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

	   COPY count

       The count is the number of rows copied.

NOTES
       COPY can only be used with plain tables, not with views. However, you
       can write COPY (SELECT * FROM viewname) TO ....

       COPY only deals with the specific table named; it does not copy data to
       or from child tables. Thus for example COPY table TO shows the same
       data as SELECT * FROM ONLY table. But COPY (SELECT * FROM table) TO ...
       can be used to dump all of the data in an inheritance hierarchy.

       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.

       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.  COPY naming a file
       is only allowed to database superusers, since it allows reading or
       writing any file that the server has privileges to access.

       Do not confuse COPY with the psql instruction \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.

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

       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.

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. If
       OIDS is specified, the OID is read or written as the first column,
       preceding the user data columns.

       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:

       +---------+----------------------------+
       |Sequence | Represents		      |
       +---------+----------------------------+
       |\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 character with  |
       |	 | that numeric code	      |
       +---------+----------------------------+
       |\xdigits | Backslash x followed by    |
       |	 | one or two hex digits      |
       |	 | specifies		      |
       |	 |	  the character 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).

       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.

       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

	   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. In particular it has a length word --
	   this will allow handling of 4-byte vs. 8-byte OIDs without too much
	   pain, and will allow OIDs to be shown as null if that ever proves
	   desirable.

       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';

       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 ]
		     [ OIDS ]
		     [ DELIMITER [ AS ] 'delimiter' ]
		     [ NULL [ AS ] 'null string' ]
		     [ CSV [ HEADER ]
			   [ QUOTE [ AS ] 'quote' ]
			   [ ESCAPE [ AS ] 'escape' ]
			   [ FORCE NOT NULL column_name [, ...] ] ] ]

	   COPY { table_name [ ( column_name [, ...] ) ] | ( query ) }
	       TO { 'filename' | STDOUT }
	       [ [ WITH ]
		     [ BINARY ]
		     [ OIDS ]
		     [ DELIMITER [ AS ] 'delimiter' ]
		     [ NULL [ AS ] 'null string' ]
		     [ CSV [ HEADER ]
			   [ QUOTE [ AS ] 'quote' ]
			   [ ESCAPE [ AS ] 'escape' ]
			   [ 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 [ WITH OIDS ]
	       FROM { 'filename' | STDIN }
	       [ [USING] DELIMITERS 'delimiter' ]
	       [ WITH NULL AS 'null string' ]

	   COPY [ BINARY ] table_name [ WITH OIDS ]
	       TO { 'filename' | STDOUT }
	       [ [USING] DELIMITERS 'delimiter' ]
	       [ WITH NULL AS 'null string' ]




PostgreSQL 9.2.24		  2017-11-06			       COPY(7)