Source of file SQL.php

<?php declare(strict_types=1);

/**

 * Query

 *

 * SQL Query Builder / Database Abstraction Layer

 *

 * PHP version 7.4

 *

 * @package     Query

 * @author      Timothy J. Warren <tim@timshomepage.net>

 * @copyright   2012 - 2020 Timothy J. Warren

 * @license     http://www.opensource.org/licenses/mit-license.html  MIT License

 * @link        https://git.timshomepage.net/aviat/Query

 * @version     3.0.0

 */

namespace Query\Drivers\Pgsql;

use Query\Drivers\AbstractSQL;

/**

 * PostgreSQL specific SQL

 */

class SQL extends AbstractSQL {

	/**

	 * Get the query plan for the sql query

	 *

	 * @param string $sql

	 * @return string

	 */

	public function explain(string $sql): string

	{

		return "EXPLAIN VERBOSE {$sql}";

	}

	/**

	 * Random ordering keyword

	 *

	 * @return string

	 */

	public function random(): string

	{

		return ' RANDOM()';

	}

	/**

	 * Returns sql to list other databases

	 *

	 * @return string

	 */

	public function dbList(): string

	{

		return <<<SQL

			SELECT "datname" FROM "pg_database"

			WHERE "datname" NOT IN ('template0','template1')

			ORDER BY "datname" ASC

SQL;

	}

	/**

	 * Returns sql to list tables

	 *

	 * @return string

	 */

	public function tableList(): string

	{

		return <<<SQL

			SELECT "table_name"

			FROM "information_schema"."tables"

			WHERE "table_type" = 'BASE TABLE'

			AND "table_schema" NOT IN

				('pg_catalog', 'information_schema');

SQL;

	}

	/**

	 * Returns sql to list system tables

	 *

	 * @return string

	 */

	public function systemTableList(): string

	{

		return <<<SQL

			SELECT "table_name"

			FROM "information_schema"."tables"

			WHERE "table_type" = 'BASE TABLE'

			AND "table_schema" IN

				('pg_catalog', 'information_schema');

SQL;

	}

	/**

	 * Returns sql to list views

	 *

	 * @return string

	 */

	public function viewList(): string

	{

		return <<<SQL

		 	SELECT "viewname" FROM "pg_views"

			WHERE "schemaname" NOT IN

				('pg_catalog', 'information_schema')

			AND "viewname" !~ '^pg_'

			ORDER BY "viewname" ASC

SQL;

	}

	/**

	 * Returns sql to list triggers

	 *

	 * @return string

	 */

	public function triggerList(): string

	{

		return <<<SQL

			SELECT *

			FROM "information_schema"."triggers"

			WHERE "trigger_schema" NOT IN

				('pg_catalog', 'information_schema')

SQL;

	}

	/**

	 * Return sql to list functions

	 *

	 * @return string

	 */

	public function functionList(): ?string

	{

		return NULL;

	}

	/**

	 * Return sql to list stored procedures

	 *

	 * @return string

	 */

	public function procedureList(): string

	{

		return <<<SQL

			SELECT "routine_name"

			FROM "information_schema"."routines"

			WHERE "specific_schema" NOT IN

				('pg_catalog', 'information_schema')

			AND "type_udt_name" != 'trigger';

SQL;

	}

	/**

	 * Return sql to list sequences

	 *

	 * @return string

	 */

	public function sequenceList(): string

	{

		return <<<SQL

			SELECT "c"."relname"

			FROM "pg_class" "c"

			WHERE "c"."relkind" = 'S'

			ORDER BY "relname" ASC

SQL;

	}

	/**

	 * Return sql to list columns of the specified table

	 *

	 * @param string $table

	 * @return string

	 */

	public function columnList(string $table): string

	{

		return <<<SQL

			SELECT ordinal_position,

				column_name,

				data_type,

				column_default,

				is_nullable,

				character_maximum_length,

				numeric_precision

			FROM information_schema.columns

			WHERE table_name = '{$table}'

			ORDER BY ordinal_position;

SQL;

	}

	/**

	 * SQL to show list of field types

	 *

	 * @return string

	 */

	public function typeList(): string

	{

		return <<<SQL

			SELECT "typname" FROM "pg_catalog"."pg_type"

			WHERE "typname" !~ '^pg_|_'

			AND "typtype" = 'b'

			ORDER BY "typname"

SQL;

	}

	/**

	 * Get the list of foreign keys for the current

	 * table

	 *

	 * @param string $table

	 * @return string

	 */

	public function fkList(string $table): string

	{

		return <<<SQL

			SELECT

				"att2"."attname" AS "child_column",

				"cl"."relname" AS "parent_table",

				"att"."attname" AS "parent_column",

				"con"."update" AS "update",

				"con"."update" AS "delete"

			FROM

				(SELECT

					unnest(con1.conkey) AS "parent",

					unnest(con1.confkey) AS "child",

					"con1"."confrelid",

					"con1"."conrelid",

					"con1"."confupdtype" as "update",

					"con1"."confdeltype" as "delete"

				FROM "pg_class" "cl"

				JOIN "pg_namespace" "ns" ON "cl"."relnamespace" = "ns"."oid"

				JOIN "pg_constraint" "con1" ON "con1"."conrelid" = "cl"."oid"

				WHERE "cl"."relname" = '{$table}'

					AND "ns"."nspname" = 'public'

					AND "con1"."contype" = 'f'

				)

				"con"

				JOIN "pg_attribute" "att" ON

					"att"."attrelid" = "con"."confrelid"

					AND "att"."attnum" = "con"."child"

				JOIN "pg_class" "cl" ON

					"cl"."oid" = "con"."confrelid"

				JOIN "pg_attribute" "att2" ON

					"att2"."attrelid" = "con"."conrelid"

					AND "att2"."attnum" = "con"."parent"

SQL;

	}

	/**

	 * Get the list of indexes for the current table

	 *

	 * @param string $table

	 * @return string

	 */

	public function indexList(string $table): string

	{

		return <<<SQL

			SELECT

				t.relname AS table_name,

				i.relname AS index_name,

				array_to_string(array_agg(a.attname), ', ') AS column_names

			FROM

				pg_class t,

				pg_class i,

				pg_index ix,

				pg_attribute a

			WHERE

				t.oid = ix.indrelid

				AND i.oid = ix.indexrelid

				AND a.attrelid = t.oid

				AND a.attnum = ANY(ix.indkey)

				AND t.relkind = 'r'

				AND t.relname = '{$table}'

			GROUP BY

				t.relname,

				i.relname

			ORDER BY

				t.relname,

				i.relname;

SQL;

	}

}