我已经看到可以使用 psql 中的以下命令将所有表转换为不区分大小写的名称：
\o /tmp/go_to_lower
select 'ALTER TABLE '||'"'||tablename||'"'||' RENAME TO ' ||
lower(tablename)||';' from pg_tables where schemaname = 'public';
psql -U username database < /tmp/go_to_lower
我一直无法找到以相同方式将所有列转换为不区分大小写的命令。如何做到这一点？
编辑：显然上面的代码只将表名转换为小写。我知道此代码 ALTER TABLE "YourTableName" RENAME TO YourTableName; 将转换为表名不区分大小写。有没有办法对列名的质量执行类似的功能？
按照与原版相同的思路，您应该能够执行以下操作。这通过从 information_schema 中提取它们，为更改生成 SQL，将其存储到文件然后再次执行 SQL 来重命名所有尚未使用小写的列。
\t on
select 'ALTER TABLE '||'"'||table_name||'"'||' RENAME COLUMN '||'"'||column_name||'"'||' TO ' || lower(column_name)||';'
from information_schema.columns
where table_schema = 'public' and lower(column_name) != column_name
\g /tmp/go_to_lower
\i /tmp/go_to_lower
By default, all you identifiers are case insensitive, and internally PostgreSQL stores them in lowercase. In case you need to have:
within your identifiers, you should use double quotes (") around your identifiers.
Please, check this bit of the PostgreSQL documentation.
EDIT: After your clarification, you can use:
SELECT 'ALTER TABLE '||quote_ident(t.relname)||' RENAME TO '||t.relname||';'
FROM pg_class t, pg_namespace s
WHERE s.oid = t.relnamespace AND s.nspname = 'public'
AND t.relkind='r' AND t.relname != lower(t.relname)
ORDER BY 1;
and for columns:
SELECT 'ALTER TABLE '||quote_ident(t.relname)||
' RENAME COLUMN '||quote_ident(a.attname)||
' TO '||a.attname||';'
FROM pg_class t, pg_namespace s, pg_attribute a
WHERE s.oid = t.relnamespace AND s.nspname = 'public'
AND t.relkind='r'
AND a.attrelid = t.oid AND NOT a.attisdropped AND a.attnum > 0
AND a.attname != lower(a.attname)
ORDER BY 1;
Then copy-paste the output into your client.
If you're using psql, you can use \t to enable rows-only mode, \o <full_file_path> to save output into the temporary file and, finally, \i <full_file_path> to execute actual statements.
我在 Database Administrators 上创建了一个 SQL 查询来执行此操作。
' '为'_'有关更多信息，请参阅，
do language plpgsql $$
declare
r record;
begin
for r in
select relname, attname
from pg_attribute a
inner join pg_class c on a.attrelid = c.oid
inner join pg_namespace n on c.relnamespace = n.oid
where
n.nspname = 'public'
and
attname != lower(attname)
and
not attisdropped
loop
execute format('
alter table %1$I rename column %2$I to %3$s
', r.relname, r.attname, lower(r.attname));
end loop;
end;
$$;
begin;在尝试这个之前发出一个。检查是否正确。然后才发出一个commit;. 如果您使用的是命名空间，请在where子句中替换它。
让我为像我这样的初学者和不习惯像 psql 这样的命令行工具的初学者添加一个使用 PgAdmin 的分步指南：
在 PgAdmin 中执行以下查询：
SELECT 'ALTER TABLE ' || quote_ident(c.table_schema) || '.'
|| quote_ident(c.table_name) || ' RENAME "' || c.column_name || '" TO ' || quote_ident(lower(c.column_name)) || ';' As ddlsql
FROM information_schema.columns As c
WHERE c.table_schema NOT IN('information_schema', 'pg_catalog')
AND c.column_name <> lower(c.column_name)
ORDER BY c.table_schema, c.table_name, c.column_name;
*来源：https ://www.postgresonline.com/article_pfriendly/141.html 。请注意，您无需在此处更改任何内容。
现在将结果导出到文本文件。
使用 Excel、记事本或您选择的任何文本编辑器打开 .csv 文件。复制除第一行（“ddlsql”）之外的所有行并将它们粘贴到 PgAdmin 中的新查询中。确保删除双引号。运行它并完成。