java + mysql與postgresql的區別之sql

在寫java應用時，遇到一個與mysql不一樣的語法錯誤

java+mysql:

String sql = "select * from t_hlprfinal_data where hltag="+tagsql+" limit 12";

 

 

java+postgresql:

 

String sql = "select * from t_hlprfinal_data where hltag='"+tagsql+"' limit 12";

如果換成與mysql一樣則會報錯：sql ERROR: syntax error at or near "client"