From 1468ecba028f04684b930cb4884870f790ce420b Mon Sep 17 00:00:00 2001 From: jian he Date: Mon, 10 Nov 2025 08:39:36 +0800 Subject: [PATCH 1/3] introduce CopyFormat refactor CopyFormatOptions Currently, COPY command format is determined by two booleans, binary and csv_mode, within CopyFormatOptions. This approach, while functional, isn't ideal for future expansion. To simplify adding new formats, we've introduced an enum CopyFormat. This makes the code cleaner and more maintainable, allowing for easier integration of additional formats down the line. The CopyFormat enum was originally contributed by Joel Jacobson joel@compiler.org, later refactored by Jian He to address various issues. discussion: https://postgr.es/m/CALvfUkBxTYy5uWPFVwpk_7ii2zgT07t3d-yR_cy4sfrrLU%3Dkcg%40mail.gmail.com discussion: https://postgr.es/m/6a04628d-0d53-41d9-9e35-5a8dc302c34c@joeconway.com --- src/backend/commands/copy.c | 50 +++++++++++++++------------- src/backend/commands/copyfrom.c | 6 ++-- src/backend/commands/copyfromparse.c | 7 ++-- src/backend/commands/copyto.c | 8 ++--- src/include/commands/copy.h | 13 ++++++-- src/tools/pgindent/typedefs.list | 1 + 6 files changed, 49 insertions(+), 36 deletions(-) diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c index 28e878c36887..d674ada98e46 100644 --- a/src/backend/commands/copy.c +++ b/src/backend/commands/copy.c @@ -564,6 +564,8 @@ ProcessCopyOptions(ParseState *pstate, opts_out = (CopyFormatOptions *) palloc0(sizeof(CopyFormatOptions)); opts_out->file_encoding = -1; + /* default format */ + opts_out->format = COPY_FORMAT_TEXT; /* Extract options from the statement node tree */ foreach(option, options) @@ -578,11 +580,11 @@ ProcessCopyOptions(ParseState *pstate, errorConflictingDefElem(defel, pstate); format_specified = true; if (strcmp(fmt, "text") == 0) - /* default format */ ; + opts_out->format = COPY_FORMAT_TEXT; else if (strcmp(fmt, "csv") == 0) - opts_out->csv_mode = true; + opts_out->format = COPY_FORMAT_CSV; else if (strcmp(fmt, "binary") == 0) - opts_out->binary = true; + opts_out->format = COPY_FORMAT_BINARY; else ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), @@ -742,31 +744,31 @@ ProcessCopyOptions(ParseState *pstate, * Check for incompatible options (must do these three before inserting * defaults) */ - if (opts_out->binary && opts_out->delim) + if (opts_out->format == COPY_FORMAT_BINARY && opts_out->delim) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ errmsg("cannot specify %s in BINARY mode", "DELIMITER"))); - if (opts_out->binary && opts_out->null_print) + if (opts_out->format == COPY_FORMAT_BINARY && opts_out->null_print) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("cannot specify %s in BINARY mode", "NULL"))); - if (opts_out->binary && opts_out->default_print) + if (opts_out->format == COPY_FORMAT_BINARY && opts_out->default_print) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("cannot specify %s in BINARY mode", "DEFAULT"))); /* Set defaults for omitted options */ if (!opts_out->delim) - opts_out->delim = opts_out->csv_mode ? "," : "\t"; + opts_out->delim = (opts_out->format == COPY_FORMAT_CSV) ? "," : "\t"; if (!opts_out->null_print) - opts_out->null_print = opts_out->csv_mode ? "" : "\\N"; + opts_out->null_print = (opts_out->format == COPY_FORMAT_CSV) ? "" : "\\N"; opts_out->null_print_len = strlen(opts_out->null_print); - if (opts_out->csv_mode) + if (opts_out->format == COPY_FORMAT_CSV) { if (!opts_out->quote) opts_out->quote = "\""; @@ -814,7 +816,7 @@ ProcessCopyOptions(ParseState *pstate, * future-proofing. Likewise we disallow all digits though only octal * digits are actually dangerous. */ - if (!opts_out->csv_mode && + if (opts_out->format != COPY_FORMAT_CSV && strchr("\\.abcdefghijklmnopqrstuvwxyz0123456789", opts_out->delim[0]) != NULL) ereport(ERROR, @@ -822,43 +824,43 @@ ProcessCopyOptions(ParseState *pstate, errmsg("COPY delimiter cannot be \"%s\"", opts_out->delim))); /* Check header */ - if (opts_out->binary && opts_out->header_line != COPY_HEADER_FALSE) + if (opts_out->format == COPY_FORMAT_BINARY && opts_out->header_line != COPY_HEADER_FALSE) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ errmsg("cannot specify %s in BINARY mode", "HEADER"))); /* Check quote */ - if (!opts_out->csv_mode && opts_out->quote != NULL) + if (opts_out->format != COPY_FORMAT_CSV && opts_out->quote != NULL) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ errmsg("COPY %s requires CSV mode", "QUOTE"))); - if (opts_out->csv_mode && strlen(opts_out->quote) != 1) + if (opts_out->format == COPY_FORMAT_CSV && strlen(opts_out->quote) != 1) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("COPY quote must be a single one-byte character"))); - if (opts_out->csv_mode && opts_out->delim[0] == opts_out->quote[0]) + if (opts_out->format == COPY_FORMAT_CSV && opts_out->delim[0] == opts_out->quote[0]) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("COPY delimiter and quote must be different"))); /* Check escape */ - if (!opts_out->csv_mode && opts_out->escape != NULL) + if (opts_out->format != COPY_FORMAT_CSV && opts_out->escape != NULL) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ errmsg("COPY %s requires CSV mode", "ESCAPE"))); - if (opts_out->csv_mode && strlen(opts_out->escape) != 1) + if (opts_out->format == COPY_FORMAT_CSV && strlen(opts_out->escape) != 1) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("COPY escape must be a single one-byte character"))); /* Check force_quote */ - if (!opts_out->csv_mode && (opts_out->force_quote || opts_out->force_quote_all)) + if (opts_out->format != COPY_FORMAT_CSV && (opts_out->force_quote || opts_out->force_quote_all)) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ @@ -872,8 +874,8 @@ ProcessCopyOptions(ParseState *pstate, "COPY FROM"))); /* Check force_notnull */ - if (!opts_out->csv_mode && (opts_out->force_notnull != NIL || - opts_out->force_notnull_all)) + if (opts_out->format != COPY_FORMAT_CSV && (opts_out->force_notnull != NIL || + opts_out->force_notnull_all)) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ @@ -888,8 +890,8 @@ ProcessCopyOptions(ParseState *pstate, "COPY TO"))); /* Check force_null */ - if (!opts_out->csv_mode && (opts_out->force_null != NIL || - opts_out->force_null_all)) + if (opts_out->format != COPY_FORMAT_CSV && (opts_out->force_null != NIL || + opts_out->force_null_all)) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ @@ -913,7 +915,7 @@ ProcessCopyOptions(ParseState *pstate, "NULL"))); /* Don't allow the CSV quote char to appear in the null string. */ - if (opts_out->csv_mode && + if (opts_out->format == COPY_FORMAT_CSV && strchr(opts_out->null_print, opts_out->quote[0]) != NULL) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), @@ -949,7 +951,7 @@ ProcessCopyOptions(ParseState *pstate, "DEFAULT"))); /* Don't allow the CSV quote char to appear in the default string. */ - if (opts_out->csv_mode && + if (opts_out->format == COPY_FORMAT_CSV && strchr(opts_out->default_print, opts_out->quote[0]) != NULL) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), @@ -966,7 +968,7 @@ ProcessCopyOptions(ParseState *pstate, errmsg("NULL specification and DEFAULT specification cannot be the same"))); } /* Check on_error */ - if (opts_out->binary && opts_out->on_error != COPY_ON_ERROR_STOP) + if (opts_out->format == COPY_FORMAT_BINARY && opts_out->on_error != COPY_ON_ERROR_STOP) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("only ON_ERROR STOP is allowed in BINARY mode"))); diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index 12781963b4f9..ba31b227d5ff 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -155,9 +155,9 @@ static const CopyFromRoutine CopyFromRoutineBinary = { static const CopyFromRoutine * CopyFromGetRoutine(const CopyFormatOptions *opts) { - if (opts->csv_mode) + if (opts->format == COPY_FORMAT_CSV) return &CopyFromRoutineCSV; - else if (opts->binary) + else if (opts->format == COPY_FORMAT_BINARY) return &CopyFromRoutineBinary; /* default is text */ @@ -261,7 +261,7 @@ CopyFromErrorCallback(void *arg) cstate->cur_relname); return; } - if (cstate->opts.binary) + if (cstate->opts.format == COPY_FORMAT_BINARY) { /* can't usefully display the data */ if (cstate->cur_attname) diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c index b1ae97b833df..578e6c0c9a2e 100644 --- a/src/backend/commands/copyfromparse.c +++ b/src/backend/commands/copyfromparse.c @@ -171,7 +171,7 @@ ReceiveCopyBegin(CopyFromState cstate) { StringInfoData buf; int natts = list_length(cstate->attnumlist); - int16 format = (cstate->opts.binary ? 1 : 0); + int16 format = (cstate->opts.format == COPY_FORMAT_BINARY ? 1 : 0); int i; pq_beginmessage(&buf, PqMsg_CopyInResponse); @@ -747,7 +747,7 @@ bool NextCopyFromRawFields(CopyFromState cstate, char ***fields, int *nfields) { return NextCopyFromRawFieldsInternal(cstate, fields, nfields, - cstate->opts.csv_mode); + cstate->opts.format == COPY_FORMAT_CSV); } /* @@ -774,7 +774,8 @@ NextCopyFromRawFieldsInternal(CopyFromState cstate, char ***fields, int *nfields bool done = false; /* only available for text or csv input */ - Assert(!cstate->opts.binary); + Assert(cstate->opts.format == COPY_FORMAT_TEXT || + cstate->opts.format == COPY_FORMAT_CSV); /* on input check that the header line is correct if needed */ if (cstate->cur_lineno == 0 && cstate->opts.header_line != COPY_HEADER_FALSE) diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c index cef452584e58..c97f0460b3e5 100644 --- a/src/backend/commands/copyto.c +++ b/src/backend/commands/copyto.c @@ -181,9 +181,9 @@ static const CopyToRoutine CopyToRoutineBinary = { static const CopyToRoutine * CopyToGetRoutine(const CopyFormatOptions *opts) { - if (opts->csv_mode) + if (opts->format == COPY_FORMAT_CSV) return &CopyToRoutineCSV; - else if (opts->binary) + else if (opts->format == COPY_FORMAT_BINARY) return &CopyToRoutineBinary; /* default is text */ @@ -220,7 +220,7 @@ CopyToTextLikeStart(CopyToState cstate, TupleDesc tupDesc) colname = NameStr(TupleDescAttr(tupDesc, attnum - 1)->attname); - if (cstate->opts.csv_mode) + if (cstate->opts.format == COPY_FORMAT_CSV) CopyAttributeOutCSV(cstate, colname, false); else CopyAttributeOutText(cstate, colname); @@ -397,7 +397,7 @@ SendCopyBegin(CopyToState cstate) { StringInfoData buf; int natts = list_length(cstate->attnumlist); - int16 format = (cstate->opts.binary ? 1 : 0); + int16 format = (cstate->opts.format == COPY_FORMAT_BINARY ? 1 : 0); int i; pq_beginmessage(&buf, PqMsg_CopyOutResponse); diff --git a/src/include/commands/copy.h b/src/include/commands/copy.h index 541176e19803..686653233b27 100644 --- a/src/include/commands/copy.h +++ b/src/include/commands/copy.h @@ -48,6 +48,16 @@ typedef enum CopyLogVerbosityChoice COPY_LOG_VERBOSITY_VERBOSE, /* logs additional messages */ } CopyLogVerbosityChoice; +/* + * Represents the format of the COPY operation. + */ +typedef enum CopyFormat +{ + COPY_FORMAT_TEXT = 0, + COPY_FORMAT_BINARY, + COPY_FORMAT_CSV, +} CopyFormat; + /* * A struct to hold COPY options, in a parsed form. All of these are related * to formatting, except for 'freeze', which doesn't really belong here, but @@ -58,9 +68,8 @@ typedef struct CopyFormatOptions /* parameters from the COPY command */ int file_encoding; /* file or remote side's character encoding, * -1 if not specified */ - bool binary; /* binary format? */ + CopyFormat format; /* format of the COPY operation */ bool freeze; /* freeze rows on loading? */ - bool csv_mode; /* Comma Separated Value format? */ int header_line; /* number of lines to skip or COPY_HEADER_XXX * value (see the above) */ char *null_print; /* NULL marker string (server encoding!) */ diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list index 23bce72ae64b..ae8ffb1c7750 100644 --- a/src/tools/pgindent/typedefs.list +++ b/src/tools/pgindent/typedefs.list @@ -516,6 +516,7 @@ ConversionLocation ConvertRowtypeExpr CookedConstraint CopyDest +CopyFormat CopyFormatOptions CopyFromRoutine CopyFromState From c80d807843c40d07f9abe8830f2a28c7b63cb8b3 Mon Sep 17 00:00:00 2001 From: jian he Date: Mon, 10 Nov 2025 08:40:26 +0800 Subject: [PATCH 2/3] json format for COPY TO JSON format is only supported with the COPY TO operation. It is incompatible with options such as HEADER, DEFAULT, NULL, DELIMITER, and several others. This has been thoroughly tested in src/test/regress/sql/copy.sql The CopyFormat enum was originally contributed by Joel Jacobson joel@compiler.org, later refactored by Jian He to address various issues, and further adapted by Junwang Zhao to support the newly introduced CopyToRoutine struct (commit 2e4127b6d2). Author: Joe Conway Reviewed-by: "Andrey M. Borodin" , Reviewed-by: Dean Rasheed , Reviewed-by: Daniel Verite , Reviewed-by: Andrew Dunstan , Reviewed-by: Davin Shearer , Reviewed-by: Masahiko Sawada , Reviewed-by: Alvaro Herrera discussion: https://postgr.es/m/CALvfUkBxTYy5uWPFVwpk_7ii2zgT07t3d-yR_cy4sfrrLU%3Dkcg%40mail.gmail.com discussion: https://postgr.es/m/6a04628d-0d53-41d9-9e35-5a8dc302c34c@joeconway.com --- doc/src/sgml/ref/copy.sgml | 13 +++-- src/backend/commands/copy.c | 72 +++++++++++++++++++++------- src/backend/commands/copyto.c | 76 ++++++++++++++++++++++++++---- src/backend/parser/gram.y | 8 ++++ src/backend/utils/adt/json.c | 5 +- src/bin/psql/tab-complete.in.c | 2 +- src/include/commands/copy.h | 1 + src/include/utils/json.h | 2 + src/test/regress/expected/copy.out | 76 ++++++++++++++++++++++++++++++ src/test/regress/sql/copy.sql | 47 ++++++++++++++++++ 10 files changed, 268 insertions(+), 34 deletions(-) diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml index fdc24b36bb8e..2d6d6802cbda 100644 --- a/doc/src/sgml/ref/copy.sgml +++ b/doc/src/sgml/ref/copy.sgml @@ -228,10 +228,15 @@ COPY { table_name [ ( text, csv (Comma Separated Values), + json (JavaScript Object Notation), or binary. The default is text. See below for details. + + The json option is allowed only in + COPY TO. + @@ -266,7 +271,7 @@ COPY { table_name [ ( CSV format. This must be a single one-byte character. - This option is not allowed when using binary format. + This option is not allowed when using binary or json format. @@ -280,7 +285,7 @@ COPY { table_name [ ( 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. + This option is not allowed when using binary or json format. @@ -303,7 +308,7 @@ COPY { table_name [ ( COPY FROM, and only when - not using binary format. + not using binary or json format. @@ -330,7 +335,7 @@ COPY { table_name [ ( COPY FROM commands. - This option is not allowed when using binary format. + This option is not allowed when using binary or json format. diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c index d674ada98e46..0ec9b22d20f2 100644 --- a/src/backend/commands/copy.c +++ b/src/backend/commands/copy.c @@ -585,6 +585,8 @@ ProcessCopyOptions(ParseState *pstate, opts_out->format = COPY_FORMAT_CSV; else if (strcmp(fmt, "binary") == 0) opts_out->format = COPY_FORMAT_BINARY; + else if (strcmp(fmt, "json") == 0) + opts_out->format = COPY_FORMAT_JSON; else ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), @@ -744,21 +746,42 @@ ProcessCopyOptions(ParseState *pstate, * Check for incompatible options (must do these three before inserting * defaults) */ - if (opts_out->format == COPY_FORMAT_BINARY && opts_out->delim) - ereport(ERROR, - (errcode(ERRCODE_SYNTAX_ERROR), - /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ - errmsg("cannot specify %s in BINARY mode", "DELIMITER"))); + if (opts_out->delim) + { + if (opts_out->format == COPY_FORMAT_BINARY) + ereport(ERROR, + errcode(ERRCODE_SYNTAX_ERROR), + /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ + errmsg("cannot specify %s in BINARY mode", "DELIMITER")); + else if (opts_out->format == COPY_FORMAT_JSON) + ereport(ERROR, + errcode(ERRCODE_SYNTAX_ERROR), + errmsg("cannot specify %s in JSON mode", "DELIMITER")); + } - if (opts_out->format == COPY_FORMAT_BINARY && opts_out->null_print) - ereport(ERROR, - (errcode(ERRCODE_SYNTAX_ERROR), - errmsg("cannot specify %s in BINARY mode", "NULL"))); + if (opts_out->null_print) + { + if (opts_out->format == COPY_FORMAT_BINARY) + ereport(ERROR, + errcode(ERRCODE_SYNTAX_ERROR), + errmsg("cannot specify %s in BINARY mode", "NULL")); + else if (opts_out->format == COPY_FORMAT_JSON) + ereport(ERROR, + errcode(ERRCODE_SYNTAX_ERROR), + errmsg("cannot specify %s in JSON mode", "NULL")); + } - if (opts_out->format == COPY_FORMAT_BINARY && opts_out->default_print) - ereport(ERROR, - (errcode(ERRCODE_SYNTAX_ERROR), - errmsg("cannot specify %s in BINARY mode", "DEFAULT"))); + if (opts_out->default_print) + { + if (opts_out->format == COPY_FORMAT_BINARY) + ereport(ERROR, + errcode(ERRCODE_SYNTAX_ERROR), + errmsg("cannot specify %s in BINARY mode", "DEFAULT")); + else if (opts_out->format == COPY_FORMAT_JSON) + ereport(ERROR, + errcode(ERRCODE_SYNTAX_ERROR), + errmsg("cannot specify %s in JSON mode", "DEFAULT")); + } /* Set defaults for omitted options */ if (!opts_out->delim) @@ -824,11 +847,18 @@ ProcessCopyOptions(ParseState *pstate, errmsg("COPY delimiter cannot be \"%s\"", opts_out->delim))); /* Check header */ - if (opts_out->format == COPY_FORMAT_BINARY && opts_out->header_line != COPY_HEADER_FALSE) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ - errmsg("cannot specify %s in BINARY mode", "HEADER"))); + if (opts_out->header_line != COPY_HEADER_FALSE) + { + if (opts_out->format == COPY_FORMAT_BINARY) + ereport(ERROR, + errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + /*- translator: %s is the name of a COPY option, e.g. ON_ERROR */ + errmsg("cannot specify %s in BINARY mode", "HEADER")); + else if(opts_out->format == COPY_FORMAT_JSON) + ereport(ERROR, + errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cannot specify %s in JSON mode", "HEADER")); + } /* Check quote */ if (opts_out->format != COPY_FORMAT_CSV && opts_out->quote != NULL) @@ -932,6 +962,12 @@ ProcessCopyOptions(ParseState *pstate, errmsg("COPY %s cannot be used with %s", "FREEZE", "COPY TO"))); + /* Check json format */ + if (opts_out->format == COPY_FORMAT_JSON && is_from) + ereport(ERROR, + errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("COPY %s mode cannot be used with %s", "json", "COPY FROM")); + if (opts_out->default_print) { if (!is_from) diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c index c97f0460b3e5..accf34e1a60a 100644 --- a/src/backend/commands/copyto.c +++ b/src/backend/commands/copyto.c @@ -26,6 +26,7 @@ #include "executor/execdesc.h" #include "executor/executor.h" #include "executor/tuptable.h" +#include "funcapi.h" #include "libpq/libpq.h" #include "libpq/pqformat.h" #include "mb/pg_wchar.h" @@ -33,6 +34,7 @@ #include "pgstat.h" #include "storage/fd.h" #include "tcop/tcopprot.h" +#include "utils/json.h" #include "utils/lsyscache.h" #include "utils/memutils.h" #include "utils/rel.h" @@ -130,6 +132,7 @@ static void CopyToCSVOneRow(CopyToState cstate, TupleTableSlot *slot); static void CopyToTextLikeOneRow(CopyToState cstate, TupleTableSlot *slot, bool is_csv); static void CopyToTextLikeEnd(CopyToState cstate); +static void CopyToJsonOneRow(CopyToState cstate, TupleTableSlot *slot); static void CopyToBinaryStart(CopyToState cstate, TupleDesc tupDesc); static void CopyToBinaryOutFunc(CopyToState cstate, Oid atttypid, FmgrInfo *finfo); static void CopyToBinaryOneRow(CopyToState cstate, TupleTableSlot *slot); @@ -149,7 +152,7 @@ static void CopySendInt16(CopyToState cstate, int16 val); /* * COPY TO routines for built-in formats. * - * CSV and text formats share the same TextLike routines except for the + * CSV and text, json formats share the same TextLike routines except for the * one-row callback. */ @@ -169,6 +172,14 @@ static const CopyToRoutine CopyToRoutineCSV = { .CopyToEnd = CopyToTextLikeEnd, }; +/* json format */ +static const CopyToRoutine CopyToRoutineJson = { + .CopyToStart = CopyToTextLikeStart, + .CopyToOutFunc = CopyToTextLikeOutFunc, + .CopyToOneRow = CopyToJsonOneRow, + .CopyToEnd = CopyToTextLikeEnd, +}; + /* binary format */ static const CopyToRoutine CopyToRoutineBinary = { .CopyToStart = CopyToBinaryStart, @@ -185,12 +196,14 @@ CopyToGetRoutine(const CopyFormatOptions *opts) return &CopyToRoutineCSV; else if (opts->format == COPY_FORMAT_BINARY) return &CopyToRoutineBinary; + else if (opts->format == COPY_FORMAT_JSON) + return &CopyToRoutineJson; /* default is text */ return &CopyToRoutineText; } -/* Implementation of the start callback for text and CSV formats */ +/* Implementation of the start callback for text, CSV, and json formats */ static void CopyToTextLikeStart(CopyToState cstate, TupleDesc tupDesc) { @@ -209,6 +222,8 @@ CopyToTextLikeStart(CopyToState cstate, TupleDesc tupDesc) ListCell *cur; bool hdr_delim = false; + Assert(cstate->opts.format != COPY_FORMAT_JSON); + foreach(cur, cstate->attnumlist) { int attnum = lfirst_int(cur); @@ -231,7 +246,7 @@ CopyToTextLikeStart(CopyToState cstate, TupleDesc tupDesc) } /* - * Implementation of the outfunc callback for text and CSV formats. Assign + * Implementation of the outfunc callback for text, CSV, and json formats. Assign * the output function data to the given *finfo. */ static void @@ -304,13 +319,46 @@ CopyToTextLikeOneRow(CopyToState cstate, CopySendTextLikeEndOfRow(cstate); } -/* Implementation of the end callback for text and CSV formats */ +/* Implementation of the end callback for text, CSV, and json formats */ static void CopyToTextLikeEnd(CopyToState cstate) { /* Nothing to do here */ } +/* Implementation of per-row callback for json format */ +static void +CopyToJsonOneRow(CopyToState cstate, TupleTableSlot *slot) +{ + Datum rowdata; + StringInfo result; + + /* + * If COPY TO source data come from query rather than plain table, we need + * copy CopyToState->QueryDesc->TupleDesc to slot->tts_tupleDescriptor. + * This is necessary because the slot's TupleDesc may change during query + * execution, and we depend on it when calling composite_to_json. + */ + if (!cstate->rel) + { + memcpy(TupleDescAttr(slot->tts_tupleDescriptor, 0), + TupleDescAttr(cstate->queryDesc->tupDesc, 0), + cstate->queryDesc->tupDesc->natts * sizeof(FormData_pg_attribute)); + + for (int i = 0; i < cstate->queryDesc->tupDesc->natts; i++) + populate_compact_attribute(slot->tts_tupleDescriptor, i); + + BlessTupleDesc(slot->tts_tupleDescriptor); + } + rowdata = ExecFetchSlotHeapTupleDatum(slot); + result = makeStringInfo(); + composite_to_json(rowdata, result, false); + + CopySendData(cstate, result->data, result->len); + + CopySendTextLikeEndOfRow(cstate); +} + /* * Implementation of the start callback for binary format. Send a header * for a binary copy. @@ -402,9 +450,21 @@ SendCopyBegin(CopyToState cstate) pq_beginmessage(&buf, PqMsg_CopyOutResponse); pq_sendbyte(&buf, format); /* overall format */ - pq_sendint16(&buf, natts); - for (i = 0; i < natts; i++) - pq_sendint16(&buf, format); /* per-column formats */ + if (cstate->opts.format != COPY_FORMAT_JSON) + { + pq_sendint16(&buf, natts); + for (i = 0; i < natts; i++) + pq_sendint16(&buf, format); /* per-column formats */ + } + else + { + /* + * JSON format is always one non-binary column + */ + pq_sendint16(&buf, 1); + pq_sendint16(&buf, 0); + } + pq_endmessage(&buf); cstate->copy_dest = COPY_FRONTEND; } @@ -504,7 +564,7 @@ CopySendEndOfRow(CopyToState cstate) } /* - * Wrapper function of CopySendEndOfRow for text and CSV formats. Sends the + * Wrapper function of CopySendEndOfRow for text, CSV, and json formats. Sends the * line termination and do common appropriate things for the end of row. */ static inline void diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index c3a0a354a9c4..dd23c0757106 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -3557,6 +3557,10 @@ copy_opt_item: { $$ = makeDefElem("format", (Node *) makeString("csv"), @1); } + | JSON + { + $$ = makeDefElem("format", (Node *) makeString("json"), @1); + } | HEADER_P { $$ = makeDefElem("header", (Node *) makeBoolean(true), @1); @@ -3639,6 +3643,10 @@ copy_generic_opt_elem: { $$ = makeDefElem($1, $2, @1); } + | FORMAT_LA copy_generic_opt_arg + { + $$ = makeDefElem("format", $2, @1); + } ; copy_generic_opt_arg: diff --git a/src/backend/utils/adt/json.c b/src/backend/utils/adt/json.c index 06dd62f00080..647adafd227a 100644 --- a/src/backend/utils/adt/json.c +++ b/src/backend/utils/adt/json.c @@ -86,8 +86,6 @@ typedef struct JsonAggState JsonUniqueBuilderState unique_check; } JsonAggState; -static void composite_to_json(Datum composite, StringInfo result, - bool use_line_feeds); static void array_dim_to_json(StringInfo result, int dim, int ndims, int *dims, const Datum *vals, const bool *nulls, int *valcount, JsonTypeCategory tcategory, Oid outfuncoid, @@ -517,8 +515,9 @@ array_to_json_internal(Datum array, StringInfo result, bool use_line_feeds) /* * Turn a composite / record into JSON. + * Exported so COPY TO can use it. */ -static void +void composite_to_json(Datum composite, StringInfo result, bool use_line_feeds) { HeapTupleHeader td; diff --git a/src/bin/psql/tab-complete.in.c b/src/bin/psql/tab-complete.in.c index 518065970379..91ead00091c9 100644 --- a/src/bin/psql/tab-complete.in.c +++ b/src/bin/psql/tab-complete.in.c @@ -3377,7 +3377,7 @@ match_previous_words(int pattern_id, /* Complete COPY FROM|TO [PROGRAM] WITH (FORMAT */ else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAnyExcept("PROGRAM"), "WITH", "(", "FORMAT") || Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM", MatchAny, "WITH", "(", "FORMAT")) - COMPLETE_WITH("binary", "csv", "text"); + COMPLETE_WITH("binary", "csv", "text", "json"); /* Complete COPY FROM [PROGRAM] filename WITH (ON_ERROR */ else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAnyExcept("PROGRAM"), "WITH", "(", "ON_ERROR") || diff --git a/src/include/commands/copy.h b/src/include/commands/copy.h index 686653233b27..85aedc267d6e 100644 --- a/src/include/commands/copy.h +++ b/src/include/commands/copy.h @@ -56,6 +56,7 @@ typedef enum CopyFormat COPY_FORMAT_TEXT = 0, COPY_FORMAT_BINARY, COPY_FORMAT_CSV, + COPY_FORMAT_JSON, } CopyFormat; /* diff --git a/src/include/utils/json.h b/src/include/utils/json.h index 49bbda7ac06a..1fa8e2ce8e2e 100644 --- a/src/include/utils/json.h +++ b/src/include/utils/json.h @@ -17,6 +17,8 @@ #include "lib/stringinfo.h" /* functions in json.c */ +extern void composite_to_json(Datum composite, StringInfo result, + bool use_line_feeds); extern void escape_json(StringInfo buf, const char *str); extern void escape_json_with_len(StringInfo buf, const char *str, int len); extern void escape_json_text(StringInfo buf, const text *txt); diff --git a/src/test/regress/expected/copy.out b/src/test/regress/expected/copy.out index 24e0f472f14a..10333357d689 100644 --- a/src/test/regress/expected/copy.out +++ b/src/test/regress/expected/copy.out @@ -73,6 +73,82 @@ copy copytest3 to stdout csv header; c1,"col with , comma","col with "" quote" 1,a,1 2,b,2 +--- test copying in JSON mode with various styles +copy copytest to stdout json; +{"style":"DOS","test":"abc\r\ndef","filler":1} +{"style":"Unix","test":"abc\ndef","filler":2} +{"style":"Mac","test":"abc\rdef","filler":3} +{"style":"esc\\ape","test":"a\\r\\\r\\\n\\nb","filler":4} +copy copytest to stdout (format json); +{"style":"DOS","test":"abc\r\ndef","filler":1} +{"style":"Unix","test":"abc\ndef","filler":2} +{"style":"Mac","test":"abc\rdef","filler":3} +{"style":"esc\\ape","test":"a\\r\\\r\\\n\\nb","filler":4} +-- all of the following should yield error +copy copytest to stdout (format json, delimiter '|'); +ERROR: cannot specify DELIMITER in JSON mode +copy copytest to stdout (format json, null '\N'); +ERROR: cannot specify NULL in JSON mode +copy copytest to stdout (format json, default '|'); +ERROR: cannot specify DEFAULT in JSON mode +copy copytest to stdout (format json, header); +ERROR: cannot specify HEADER in JSON mode +copy copytest to stdout (format json, header 1); +ERROR: cannot specify HEADER in JSON mode +copy copytest to stdout (format json, quote '"'); +ERROR: COPY QUOTE requires CSV mode +copy copytest to stdout (format json, escape '"'); +ERROR: COPY ESCAPE requires CSV mode +copy copytest to stdout (format json, force_quote *); +ERROR: COPY FORCE_QUOTE requires CSV mode +copy copytest to stdout (format json, force_not_null *); +ERROR: COPY FORCE_NOT_NULL requires CSV mode +copy copytest to stdout (format json, force_null *); +ERROR: COPY FORCE_NULL requires CSV mode +copy copytest to stdout (format json, on_error ignore); +ERROR: COPY ON_ERROR cannot be used with COPY TO +LINE 1: copy copytest to stdout (format json, on_error ignore); + ^ +copy copytest from stdin(format json); +ERROR: COPY json mode cannot be used with COPY FROM +-- all of the above should yield error +-- embedded escaped characters +create temp table copyjsontest ( + id bigserial, + f1 text, + f2 timestamptz); +insert into copyjsontest + select g.i, + CASE WHEN g.i % 2 = 0 THEN + 'line with '' in it: ' || g.i::text + ELSE + 'line with " in it: ' || g.i::text + END, + 'Mon Feb 10 17:32:01 1997 PST' + from generate_series(1,5) as g(i); +insert into copyjsontest (f1) values +(E'aaa\"bbb'::text), +(E'aaa\\bbb'::text), +(E'aaa\/bbb'::text), +(E'aaa\bbbb'::text), +(E'aaa\fbbb'::text), +(E'aaa\nbbb'::text), +(E'aaa\rbbb'::text), +(E'aaa\tbbb'::text); +copy copyjsontest to stdout json; +{"id":1,"f1":"line with \" in it: 1","f2":"1997-02-10T17:32:01-08:00"} +{"id":2,"f1":"line with ' in it: 2","f2":"1997-02-10T17:32:01-08:00"} +{"id":3,"f1":"line with \" in it: 3","f2":"1997-02-10T17:32:01-08:00"} +{"id":4,"f1":"line with ' in it: 4","f2":"1997-02-10T17:32:01-08:00"} +{"id":5,"f1":"line with \" in it: 5","f2":"1997-02-10T17:32:01-08:00"} +{"id":1,"f1":"aaa\"bbb","f2":null} +{"id":2,"f1":"aaa\\bbb","f2":null} +{"id":3,"f1":"aaa/bbb","f2":null} +{"id":4,"f1":"aaa\bbbb","f2":null} +{"id":5,"f1":"aaa\fbbb","f2":null} +{"id":6,"f1":"aaa\nbbb","f2":null} +{"id":7,"f1":"aaa\rbbb","f2":null} +{"id":8,"f1":"aaa\tbbb","f2":null} create temp table copytest4 ( c1 int, "colname with tab: " text); diff --git a/src/test/regress/sql/copy.sql b/src/test/regress/sql/copy.sql index 676a8b342b56..80799e2ead95 100644 --- a/src/test/regress/sql/copy.sql +++ b/src/test/regress/sql/copy.sql @@ -82,6 +82,53 @@ this is just a line full of junk that would error out if parsed copy copytest3 to stdout csv header; +--- test copying in JSON mode with various styles +copy copytest to stdout json; +copy copytest to stdout (format json); + +-- all of the following should yield error +copy copytest to stdout (format json, delimiter '|'); +copy copytest to stdout (format json, null '\N'); +copy copytest to stdout (format json, default '|'); +copy copytest to stdout (format json, header); +copy copytest to stdout (format json, header 1); +copy copytest to stdout (format json, quote '"'); +copy copytest to stdout (format json, escape '"'); +copy copytest to stdout (format json, force_quote *); +copy copytest to stdout (format json, force_not_null *); +copy copytest to stdout (format json, force_null *); +copy copytest to stdout (format json, on_error ignore); +copy copytest from stdin(format json); +-- all of the above should yield error + +-- embedded escaped characters +create temp table copyjsontest ( + id bigserial, + f1 text, + f2 timestamptz); + +insert into copyjsontest + select g.i, + CASE WHEN g.i % 2 = 0 THEN + 'line with '' in it: ' || g.i::text + ELSE + 'line with " in it: ' || g.i::text + END, + 'Mon Feb 10 17:32:01 1997 PST' + from generate_series(1,5) as g(i); + +insert into copyjsontest (f1) values +(E'aaa\"bbb'::text), +(E'aaa\\bbb'::text), +(E'aaa\/bbb'::text), +(E'aaa\bbbb'::text), +(E'aaa\fbbb'::text), +(E'aaa\nbbb'::text), +(E'aaa\rbbb'::text), +(E'aaa\tbbb'::text); + +copy copyjsontest to stdout json; + create temp table copytest4 ( c1 int, "colname with tab: " text); From f65425099984ffb7be3ee9c4bffe1c6f7f215f9b Mon Sep 17 00:00:00 2001 From: jian he Date: Wed, 30 Jul 2025 19:50:41 +0800 Subject: [PATCH 3/3] Add option force_array for COPY JSON FORMAT force_array option can only be used in COPY TO with JSON format. it make the output json output behave like json array type. refactored by Junwang Zhao to adapt the newly introduced CopyToRoutine struct(2e4127b6d2). Author: Joe Conway discussion: https://postgr.es/m/CALvfUkBxTYy5uWPFVwpk_7ii2zgT07t3d-yR_cy4sfrrLU%3Dkcg%40mail.gmail.com discussion: https://postgr.es/m/6a04628d-0d53-41d9-9e35-5a8dc302c34c@joeconway.com --- doc/src/sgml/ref/copy.sgml | 14 +++++++++++ src/backend/commands/copy.c | 13 +++++++++++ src/backend/commands/copyto.c | 37 +++++++++++++++++++++++++++++- src/bin/psql/tab-complete.in.c | 2 +- src/include/commands/copy.h | 1 + src/test/regress/expected/copy.out | 23 +++++++++++++++++++ src/test/regress/sql/copy.sql | 8 +++++++ 7 files changed, 96 insertions(+), 2 deletions(-) diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml index 2d6d6802cbda..d8d9fb173b47 100644 --- a/doc/src/sgml/ref/copy.sgml +++ b/doc/src/sgml/ref/copy.sgml @@ -40,6 +40,7 @@ COPY { table_name [ ( boolean | integer | MATCH ] QUOTE 'quote_character' ESCAPE 'escape_character' + FORCE_ARRAY [ boolean ] FORCE_QUOTE { ( column_name [, ...] ) | * } FORCE_NOT_NULL { ( column_name [, ...] ) | * } FORCE_NULL { ( column_name [, ...] ) | * } @@ -366,6 +367,19 @@ COPY { table_name [ ( + + FORCE_ARRAY + + + Force output of square brackets as array decorations at the beginning + and end of output, and commas between the rows. It is allowed only in + COPY TO, and only when using + json format. The default is + false. + + + + FORCE_QUOTE diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c index 0ec9b22d20f2..6f9ae3fbfd7b 100644 --- a/src/backend/commands/copy.c +++ b/src/backend/commands/copy.c @@ -557,6 +557,7 @@ ProcessCopyOptions(ParseState *pstate, bool on_error_specified = false; bool log_verbosity_specified = false; bool reject_limit_specified = false; + bool force_array_specified = false; ListCell *option; /* Support external use for option sanity checking */ @@ -713,6 +714,13 @@ ProcessCopyOptions(ParseState *pstate, defel->defname), parser_errposition(pstate, defel->location))); } + else if (strcmp(defel->defname, "force_array") == 0) + { + if (force_array_specified) + errorConflictingDefElem(defel, pstate); + force_array_specified = true; + opts_out->force_array = defGetBoolean(defel); + } else if (strcmp(defel->defname, "on_error") == 0) { if (on_error_specified) @@ -968,6 +976,11 @@ ProcessCopyOptions(ParseState *pstate, errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("COPY %s mode cannot be used with %s", "json", "COPY FROM")); + if (opts_out->format != COPY_FORMAT_JSON && opts_out->force_array) + ereport(ERROR, + errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("COPY %s can only used with JSON mode", "FORCE_ARRAY")); + if (opts_out->default_print) { if (!is_from) diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c index accf34e1a60a..b58c5bdf987e 100644 --- a/src/backend/commands/copyto.c +++ b/src/backend/commands/copyto.c @@ -86,6 +86,10 @@ typedef struct CopyToStateData List *attnumlist; /* integer list of attnums to copy */ char *filename; /* filename, or NULL for STDOUT */ bool is_program; /* is 'filename' a program to popen? */ + + /* need delimiter to start next json array element */ + bool json_row_delim_needed; + copy_data_dest_cb data_dest_cb; /* function for writing data */ CopyFormatOptions opts; @@ -133,6 +137,7 @@ static void CopyToTextLikeOneRow(CopyToState cstate, TupleTableSlot *slot, bool is_csv); static void CopyToTextLikeEnd(CopyToState cstate); static void CopyToJsonOneRow(CopyToState cstate, TupleTableSlot *slot); +static void CopyToJsonEnd(CopyToState cstate); static void CopyToBinaryStart(CopyToState cstate, TupleDesc tupDesc); static void CopyToBinaryOutFunc(CopyToState cstate, Oid atttypid, FmgrInfo *finfo); static void CopyToBinaryOneRow(CopyToState cstate, TupleTableSlot *slot); @@ -177,7 +182,7 @@ static const CopyToRoutine CopyToRoutineJson = { .CopyToStart = CopyToTextLikeStart, .CopyToOutFunc = CopyToTextLikeOutFunc, .CopyToOneRow = CopyToJsonOneRow, - .CopyToEnd = CopyToTextLikeEnd, + .CopyToEnd = CopyToJsonEnd, }; /* binary format */ @@ -243,6 +248,16 @@ CopyToTextLikeStart(CopyToState cstate, TupleDesc tupDesc) CopySendTextLikeEndOfRow(cstate); } + + /* + * If JSON has been requested, and FORCE_ARRAY has been specified send the + * opening bracket. + */ + if (cstate->opts.format == COPY_FORMAT_JSON && cstate->opts.force_array) + { + CopySendChar(cstate, '['); + CopySendTextLikeEndOfRow(cstate); + } } /* @@ -354,11 +369,31 @@ CopyToJsonOneRow(CopyToState cstate, TupleTableSlot *slot) result = makeStringInfo(); composite_to_json(rowdata, result, false); + if (cstate->json_row_delim_needed && cstate->opts.force_array) + CopySendChar(cstate, ','); + else if (cstate->opts.force_array) + { + /* first row needs no delimiter */ + CopySendChar(cstate, ' '); + cstate->json_row_delim_needed = true; + } + CopySendData(cstate, result->data, result->len); CopySendTextLikeEndOfRow(cstate); } +/* Implementation of the end callback for json format */ +static void +CopyToJsonEnd(CopyToState cstate) +{ + if (cstate->opts.force_array) + { + CopySendChar(cstate, ']'); + CopySendTextLikeEndOfRow(cstate); + } +} + /* * Implementation of the start callback for binary format. Send a header * for a binary copy. diff --git a/src/bin/psql/tab-complete.in.c b/src/bin/psql/tab-complete.in.c index 91ead00091c9..c451f45feabd 100644 --- a/src/bin/psql/tab-complete.in.c +++ b/src/bin/psql/tab-complete.in.c @@ -1232,7 +1232,7 @@ Copy_common_options, "DEFAULT", "FORCE_NOT_NULL", "FORCE_NULL", "FREEZE", \ /* COPY TO options */ #define Copy_to_options \ -Copy_common_options, "FORCE_QUOTE" +Copy_common_options, "FORCE_QUOTE", "FORCE_ARRAY" /* * These object types were introduced later than our support cutoff of diff --git a/src/include/commands/copy.h b/src/include/commands/copy.h index 85aedc267d6e..7274b0d3ca5d 100644 --- a/src/include/commands/copy.h +++ b/src/include/commands/copy.h @@ -87,6 +87,7 @@ typedef struct CopyFormatOptions List *force_notnull; /* list of column names */ bool force_notnull_all; /* FORCE_NOT_NULL *? */ bool *force_notnull_flags; /* per-column CSV FNN flags */ + bool force_array; /* add JSON array decorations */ List *force_null; /* list of column names */ bool force_null_all; /* FORCE_NULL *? */ bool *force_null_flags; /* per-column CSV FN flags */ diff --git a/src/test/regress/expected/copy.out b/src/test/regress/expected/copy.out index 10333357d689..8becc70ee7a4 100644 --- a/src/test/regress/expected/copy.out +++ b/src/test/regress/expected/copy.out @@ -112,6 +112,29 @@ LINE 1: copy copytest to stdout (format json, on_error ignore); copy copytest from stdin(format json); ERROR: COPY json mode cannot be used with COPY FROM -- all of the above should yield error +--Error +copy copytest to stdout (format csv, force_array true); +ERROR: COPY FORCE_ARRAY can only used with JSON mode +--ok +copy copytest to stdout (format json, force_array); +[ + {"style":"DOS","test":"abc\r\ndef","filler":1} +,{"style":"Unix","test":"abc\ndef","filler":2} +,{"style":"Mac","test":"abc\rdef","filler":3} +,{"style":"esc\\ape","test":"a\\r\\\r\\\n\\nb","filler":4} +] +copy copytest to stdout (format json, force_array true); +[ + {"style":"DOS","test":"abc\r\ndef","filler":1} +,{"style":"Unix","test":"abc\ndef","filler":2} +,{"style":"Mac","test":"abc\rdef","filler":3} +,{"style":"esc\\ape","test":"a\\r\\\r\\\n\\nb","filler":4} +] +copy copytest to stdout (format json, force_array false); +{"style":"DOS","test":"abc\r\ndef","filler":1} +{"style":"Unix","test":"abc\ndef","filler":2} +{"style":"Mac","test":"abc\rdef","filler":3} +{"style":"esc\\ape","test":"a\\r\\\r\\\n\\nb","filler":4} -- embedded escaped characters create temp table copyjsontest ( id bigserial, diff --git a/src/test/regress/sql/copy.sql b/src/test/regress/sql/copy.sql index 80799e2ead95..6a14cfc6e688 100644 --- a/src/test/regress/sql/copy.sql +++ b/src/test/regress/sql/copy.sql @@ -101,6 +101,14 @@ copy copytest to stdout (format json, on_error ignore); copy copytest from stdin(format json); -- all of the above should yield error +--Error +copy copytest to stdout (format csv, force_array true); + +--ok +copy copytest to stdout (format json, force_array); +copy copytest to stdout (format json, force_array true); +copy copytest to stdout (format json, force_array false); + -- embedded escaped characters create temp table copyjsontest ( id bigserial,