这些示例包含类似于旧版 MySQL 函数的用户定义函数。
示例 #1 PostgreSQL 用户定义函数示例
<?php
// 此函数应该是不必要的，因为PostgreSQL连接绑定数据库。
function pg_list_dbs($db)
{
assert(is_resource($db));
$query = '
SELECT
d.datname as "Name",
u.usename as "Owner",
pg_encoding_to_char(d.encoding) as "Encoding"
FROM
pg_database d LEFT JOIN pg_user u ON d.datdba = u.usesysid
ORDER BY 1;
';
return pg_query($db, $query);
}
// 列出表。
function pg_list_tables($db)
{
assert(is_resource($db));
$query = "
SELECT
c.relname as \"Name\",
CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' END as \"Type\",
u.usename as \"Owner\"
FROM
pg_class c LEFT JOIN pg_user u ON c.relowner = u.usesysid
WHERE
c.relkind IN ('r','v','S','')
AND c.relname !~ '^pg_'
ORDER BY 1;
";
return pg_query($db, $query);
}
// 另见 pg_meta_data()。它返回字段定义作为数组。
function pg_list_fields($db, $table)
{
assert(is_resource($db));
$query = "
SELECT
a.attname,
format_type(a.atttypid, a.atttypmod),
a.attnotnull,
a.atthasdef,
a.attnum
FROM
pg_class c,
pg_attribute a
WHERE
c.relname = '".$table."'
AND a.attnum > 0 AND a.attrelid = c.oid
ORDER BY a.attnum;
";
return pg_query($db, $query);
}
?>