如何在 psql 的命令行查询中转义单引号？

Question

我用谷歌搜索了很多但是..

如何在 psql 的命令行查询中转义单引号？

psql -t -A -F $'\t' postgresql://zzzz:5432/casedb -U qqqq -c 'select id,ext_ids ->> 'qwe' as qwe from data ORDER BY qwe' > /jdata/qwe.tab

结果出错

ERROR:  column "qwe" does not exist
LINE 1: select id,ext_ids ->> qwe as qwe from data...

Answer 1

您可以只对 shell 引号使用双引号 (")，对 SQL 引号使用单引号 (')：

psql -t -A -F $'\t' postgresql://zzzz:5432/casedb -U qqqq -c "select id,ext_ids ->> 'qwe' as qwe from data ORDER BY qwe" > /jdata/qwe.tab
# Here ------------------------------------------------------^---------------------------------------------------------^

Answer 2

在 Postgres 中你可以使用 dollar-quoted strings:

select id,ext_ids ->> $$qwe$$ as qwe from data ORDER BY qwe;
-- or
select id,ext_ids ->> $anything$qwe$anything$ as qwe from data ORDER BY qwe;