diff --git a/doc/src/sgml/func/func-info.sgml b/doc/src/sgml/func/func-info.sgml index d4508114a48ea..115724616cd0a 100644 --- a/doc/src/sgml/func/func-info.sgml +++ b/doc/src/sgml/func/func-info.sgml @@ -3797,4 +3797,59 @@ acl | {postgres=arwdDxtm/postgres,foo=r/postgres} + + Get Object DDL Functions + + + The functions described in + return the Data Definition Language (DDL) statement for any given database object. + This feature is implemented as a set of distinct functions for each object type. + + + + Get Object DDL Functions + + + + + Function + + + Description + + + + + + + + + pg_get_database_ddl + + pg_get_database_ddl + ( databaseID regdatabase, pretty boolean ) + text + + + Reconstructs the CREATE DATABASE statement from the + system catalogs for a specified database name or database oid. The + result is a comprehensive CREATE DATABASE statement. + + + + +
+ + + Most of the functions that reconstruct (decompile) database objects have an + optional pretty flag, which if + true causes the result to be + pretty-printed. Pretty-printing adds tab character and new + line character for legibility. Passing false for the + pretty parameter yields the same result as omitting + the parameter. + + + + diff --git a/src/backend/catalog/system_functions.sql b/src/backend/catalog/system_functions.sql index 2d946d6d9e9bc..9fb02a2017d00 100644 --- a/src/backend/catalog/system_functions.sql +++ b/src/backend/catalog/system_functions.sql @@ -657,6 +657,12 @@ LANGUAGE INTERNAL STRICT VOLATILE PARALLEL UNSAFE AS 'pg_replication_origin_session_setup'; +CREATE OR REPLACE FUNCTION + pg_get_database_ddl(databaseID regdatabase, pretty bool DEFAULT false) +RETURNS text +LANGUAGE internal +AS 'pg_get_database_ddl'; + -- -- The default permissions for functions mean that anyone can execute them. -- A number of functions shouldn't be executable by just anyone, but rather diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index 9f85eb86da1cb..f73734f3ac0b6 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -28,6 +28,7 @@ #include "catalog/pg_authid.h" #include "catalog/pg_collation.h" #include "catalog/pg_constraint.h" +#include "catalog/pg_database.h" #include "catalog/pg_depend.h" #include "catalog/pg_language.h" #include "catalog/pg_opclass.h" @@ -57,6 +58,7 @@ #include "rewrite/rewriteHandler.h" #include "rewrite/rewriteManip.h" #include "rewrite/rewriteSupport.h" +#include "utils/acl.h" #include "utils/array.h" #include "utils/builtins.h" #include "utils/fmgroids.h" @@ -94,6 +96,10 @@ ((pretty) ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) \ : PRETTYFLAG_INDENT) +#define GET_DDL_PRETTY_FLAGS(pretty) \ + ((pretty) ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) \ + : 0) + /* Default line length for pretty-print wrapping: 0 means wrap always */ #define WRAP_COLUMN_DEFAULT 0 @@ -546,6 +552,11 @@ static void get_json_table_nested_columns(TableFunc *tf, JsonTablePlan *plan, deparse_context *context, bool showimplicit, bool needcomma); +static void get_formatted_string(StringInfo buf, + int prettyFlags, + int nTabChars, + const char *fmt,...) pg_attribute_printf(4, 5); +static char *pg_get_database_ddl_worker(Oid dbOid, int prettyFlags); #define only_marker(rte) ((rte)->inh ? "" : "ONLY ") @@ -13743,3 +13754,181 @@ get_range_partbound_string(List *bound_datums) return buf.data; } + +/* + * get_formatted_string + * + * Return a formatted version of the string. + * + * prettyFlags - Based on prettyFlags the output includes tabs (\t) and + * newlines (\n). + * nTabChars - indent with specified number of tab characters. + * fmt - printf-style format string used by appendStringInfoVA. + */ +static void +get_formatted_string(StringInfo buf, int prettyFlags, int nTabChars, const char *fmt,...) +{ + va_list args; + + if (prettyFlags & PRETTYFLAG_INDENT) + { + appendStringInfoChar(buf, '\n'); + /* Indent with tabs */ + for (int i = 0; i < nTabChars; i++) + { + appendStringInfoChar(buf, '\t'); + } + } + else + appendStringInfoChar(buf, ' '); + + va_start(args, fmt); + appendStringInfoVA(buf, fmt, args); + va_end(args); +} + +/* + * pg_get_database_ddl + * + * Generate a CREATE DATABASE statement for the specified database name or oid. + * + * databaseID - OID/Name of the database for which to generate the DDL. + * pretty - If true, format the DDL with indentation and line breaks. + */ +Datum +pg_get_database_ddl(PG_FUNCTION_ARGS) +{ + Oid dbOid = PG_GETARG_OID(0); + bool pretty = PG_GETARG_BOOL(1); + int prettyFlags; + char *res; + + prettyFlags = GET_DDL_PRETTY_FLAGS(pretty); + res = pg_get_database_ddl_worker(dbOid, prettyFlags); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +static char * +pg_get_database_ddl_worker(Oid dbOid, int prettyFlags) +{ + char *dbOwner = NULL; + bool attrIsNull; + Datum dbValue; + HeapTuple tupleDatabase; + Form_pg_database dbForm; + StringInfoData buf; + AclResult aclresult; + + /* + * User must have connect privilege for target database. + */ + aclresult = object_aclcheck(DatabaseRelationId, dbOid, GetUserId(), + ACL_CONNECT); + if (aclresult != ACLCHECK_OK && + !has_privs_of_role(GetUserId(), ROLE_PG_READ_ALL_STATS)) + { + aclcheck_error(aclresult, OBJECT_DATABASE, + get_database_name(dbOid)); + } + + /* Look up the database in pg_database */ + tupleDatabase = SearchSysCache1(DATABASEOID, ObjectIdGetDatum(dbOid)); + if (!HeapTupleIsValid(tupleDatabase)) + ereport(ERROR, + errcode(ERRCODE_UNDEFINED_OBJECT), + errmsg("database with oid %u does not exist", dbOid)); + + dbForm = (Form_pg_database) GETSTRUCT(tupleDatabase); + + initStringInfo(&buf); + + /* Look up the owner in the system catalog */ + if (OidIsValid(dbForm->datdba)) + dbOwner = GetUserNameFromId(dbForm->datdba, false); + + /* Build the CREATE DATABASE statement */ + appendStringInfo(&buf, "CREATE DATABASE %s", + quote_identifier(dbForm->datname.data)); + get_formatted_string(&buf, prettyFlags, 1, "WITH OWNER = %s", + quote_identifier(dbOwner)); + + if (dbForm->encoding != 0) + get_formatted_string(&buf, prettyFlags, 2, "ENCODING = %s", + quote_identifier(pg_encoding_to_char(dbForm->encoding))); + + /* Fetch the value of LC_COLLATE */ + dbValue = SysCacheGetAttr(DATABASEOID, tupleDatabase, + Anum_pg_database_datcollate, &attrIsNull); + if (!attrIsNull) + get_formatted_string(&buf, prettyFlags, 2, "LC_COLLATE = %s", + quote_identifier(TextDatumGetCString(dbValue))); + + /* Fetch the value of LC_CTYPE */ + dbValue = SysCacheGetAttr(DATABASEOID, tupleDatabase, + Anum_pg_database_datctype, &attrIsNull); + if (!attrIsNull) + get_formatted_string(&buf, prettyFlags, 2, "LC_CTYPE = %s", + quote_identifier(TextDatumGetCString(dbValue))); + + /* Fetch the value of LOCALE */ + dbValue = SysCacheGetAttr(DATABASEOID, tupleDatabase, + Anum_pg_database_datlocale, &attrIsNull); + if (!attrIsNull && dbForm->datlocprovider == COLLPROVIDER_BUILTIN) + get_formatted_string(&buf, prettyFlags, 2, "BUILTIN_LOCALE = %s", + quote_identifier(TextDatumGetCString(dbValue))); + else if (!attrIsNull && dbForm->datlocprovider == COLLPROVIDER_ICU) + get_formatted_string(&buf, prettyFlags, 2, "ICU_LOCALE = %s", + quote_identifier(TextDatumGetCString(dbValue))); + + /* Fetch the value of ICU_RULES */ + dbValue = SysCacheGetAttr(DATABASEOID, tupleDatabase, + Anum_pg_database_daticurules, &attrIsNull); + if (!attrIsNull && dbForm->datlocprovider == COLLPROVIDER_ICU) + get_formatted_string(&buf, prettyFlags, 2, "ICU_RULES = %s", + quote_identifier(TextDatumGetCString(dbValue))); + + /* Fetch the value of COLLATION_VERSION */ + dbValue = SysCacheGetAttr(DATABASEOID, tupleDatabase, + Anum_pg_database_datcollversion, &attrIsNull); + if (!attrIsNull) + get_formatted_string(&buf, prettyFlags, 2, "COLLATION_VERSION = %s", + quote_identifier(TextDatumGetCString(dbValue))); + + /* Set the appropriate LOCALE_PROVIDER */ + if (dbForm->datlocprovider == COLLPROVIDER_BUILTIN) + get_formatted_string(&buf, prettyFlags, 2, "LOCALE_PROVIDER = 'builtin'"); + else if (dbForm->datlocprovider == COLLPROVIDER_ICU) + get_formatted_string(&buf, prettyFlags, 2, "LOCALE_PROVIDER = 'icu'"); + else + get_formatted_string(&buf, prettyFlags, 2, "LOCALE_PROVIDER = 'libc'"); + + /* Get the tablespace name respective to the given tablespace oid */ + if (OidIsValid(dbForm->dattablespace)) + { + char *dbTablespace = get_tablespace_name(dbForm->dattablespace); + + if (dbTablespace) + get_formatted_string(&buf, prettyFlags, 2, "TABLESPACE = %s", + quote_identifier(dbTablespace)); + } + + get_formatted_string(&buf, prettyFlags, 2, "ALLOW_CONNECTIONS = %s", + dbForm->datallowconn ? "true" : "false"); + + get_formatted_string(&buf, prettyFlags, 2, "CONNECTION LIMIT = %d", + dbForm->datconnlimit); + + if (dbForm->datistemplate) + get_formatted_string(&buf, prettyFlags, 2, "IS_TEMPLATE = %s", + dbForm->datistemplate ? "true" : "false"); + + appendStringInfoChar(&buf, ';'); + + ReleaseSysCache(tupleDatabase); + + return buf.data; +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index fd9448ec7b980..c3008bd128223 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -4021,6 +4021,9 @@ proname => 'pg_get_function_sqlbody', provolatile => 's', prorettype => 'text', proargtypes => 'oid', prosrc => 'pg_get_function_sqlbody' }, +{ oid => '9492', descr => 'get CREATE statement for database name and oid', + proname => 'pg_get_database_ddl', prorettype => 'text', + proargtypes => 'regdatabase bool', prosrc => 'pg_get_database_ddl' }, { oid => '1686', descr => 'list of SQL keywords', proname => 'pg_get_keywords', procost => '10', prorows => '500', diff --git a/src/test/regress/expected/database.out b/src/test/regress/expected/database.out index 6b879b0f62a75..e0dac8d89e2c7 100644 --- a/src/test/regress/expected/database.out +++ b/src/test/regress/expected/database.out @@ -1,3 +1,49 @@ +-- +-- Reconsturct DDL +-- +-- To produce stable regression test output, it's usually necessary to +-- ignore collation and locale related details. This filter +-- functions removes collation and locale related details. +CREATE OR REPLACE FUNCTION ddl_filter(ddl_input TEXT) +RETURNS TEXT AS $$ +DECLARE + cleaned_ddl TEXT; +BEGIN + -- Remove LC_COLLATE assignments + cleaned_ddl := regexp_replace( + ddl_input, + '\s*LC_COLLATE\s*=\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + -- Remove LC_CTYPE assignments + cleaned_ddl := regexp_replace( + cleaned_ddl, + '\s*LC_CTYPE\s*=\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + -- Remove %LOCALE% placeholders + cleaned_ddl := regexp_replace( + cleaned_ddl, + '\s*\S*LOCALE\S*\s*=?\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + -- Remove %COLLATION% placeholders + cleaned_ddl := regexp_replace( + cleaned_ddl, + '\s*\S*COLLATION\S*\s*=?\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + RETURN cleaned_ddl; +END; +$$ LANGUAGE plpgsql; CREATE DATABASE regression_tbd ENCODING utf8 LC_COLLATE "C" LC_CTYPE "C" TEMPLATE template0; ALTER DATABASE regression_tbd RENAME TO regression_utf8; @@ -16,6 +62,37 @@ CREATE ROLE regress_datdba_before; CREATE ROLE regress_datdba_after; ALTER DATABASE regression_utf8 OWNER TO regress_datdba_before; REASSIGN OWNED BY regress_datdba_before TO regress_datdba_after; +-- Test pg_get_database_ddl +-- Database doesn't exists +SELECT pg_get_database_ddl('regression_database', false); +ERROR: database "regression_database" does not exist +LINE 1: SELECT pg_get_database_ddl('regression_database', false); + ^ +-- Test NULL value +SELECT pg_get_database_ddl(NULL); + pg_get_database_ddl +--------------------- + +(1 row) + +-- Without pretty +SELECT ddl_filter(pg_get_database_ddl('regression_utf8')); + ddl_filter +-------------------------------------------------------------------------------------------------------------------------------------------------------------- + CREATE DATABASE regression_utf8 WITH OWNER = regress_datdba_after ENCODING = "UTF8" TABLESPACE = pg_default ALLOW_CONNECTIONS = true CONNECTION LIMIT = 123; +(1 row) + +-- With Pretty formatted +\pset format unaligned +SELECT ddl_filter(pg_get_database_ddl('regression_utf8', true)); +ddl_filter +CREATE DATABASE regression_utf8 + WITH OWNER = regress_datdba_after + ENCODING = "UTF8" + TABLESPACE = pg_default + ALLOW_CONNECTIONS = true + CONNECTION LIMIT = 123; +(1 row) DROP DATABASE regression_utf8; DROP ROLE regress_datdba_before; DROP ROLE regress_datdba_after; diff --git a/src/test/regress/sql/database.sql b/src/test/regress/sql/database.sql index 4ef361272911e..392a4d96bb5e0 100644 --- a/src/test/regress/sql/database.sql +++ b/src/test/regress/sql/database.sql @@ -1,3 +1,51 @@ +-- +-- Reconsturct DDL +-- +-- To produce stable regression test output, it's usually necessary to +-- ignore collation and locale related details. This filter +-- functions removes collation and locale related details. + +CREATE OR REPLACE FUNCTION ddl_filter(ddl_input TEXT) +RETURNS TEXT AS $$ +DECLARE + cleaned_ddl TEXT; +BEGIN + -- Remove LC_COLLATE assignments + cleaned_ddl := regexp_replace( + ddl_input, + '\s*LC_COLLATE\s*=\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + -- Remove LC_CTYPE assignments + cleaned_ddl := regexp_replace( + cleaned_ddl, + '\s*LC_CTYPE\s*=\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + -- Remove %LOCALE% placeholders + cleaned_ddl := regexp_replace( + cleaned_ddl, + '\s*\S*LOCALE\S*\s*=?\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + -- Remove %COLLATION% placeholders + cleaned_ddl := regexp_replace( + cleaned_ddl, + '\s*\S*COLLATION\S*\s*=?\s*([''"])[^''"]*\1', + '', + 'gi' + ); + + RETURN cleaned_ddl; +END; +$$ LANGUAGE plpgsql; + CREATE DATABASE regression_tbd ENCODING utf8 LC_COLLATE "C" LC_CTYPE "C" TEMPLATE template0; ALTER DATABASE regression_tbd RENAME TO regression_utf8; @@ -19,6 +67,20 @@ CREATE ROLE regress_datdba_after; ALTER DATABASE regression_utf8 OWNER TO regress_datdba_before; REASSIGN OWNED BY regress_datdba_before TO regress_datdba_after; +-- Test pg_get_database_ddl +-- Database doesn't exists +SELECT pg_get_database_ddl('regression_database', false); + +-- Test NULL value +SELECT pg_get_database_ddl(NULL); + +-- Without pretty +SELECT ddl_filter(pg_get_database_ddl('regression_utf8')); + +-- With Pretty formatted +\pset format unaligned +SELECT ddl_filter(pg_get_database_ddl('regression_utf8', true)); + DROP DATABASE regression_utf8; DROP ROLE regress_datdba_before; DROP ROLE regress_datdba_after;