liquibase-core/src/main/java/liquibase/database/core/PostgresDatabase.java
protected boolean hasMixedCase(String tableName) {
        if (tableName == null) {
            return false;
        }
        return StringUtil.hasUpperCase(tableName) && StringUtil.hasLowerCase(tableName);
    }
protected boolean hasMixedCase(String tableName) {
        if (tableName == null) {
            return false;
        }
        return StringUtil.hasUpperCase(tableName) && StringUtil.hasLowerCase(tableName);
    }
/*
Check if given string has case problems according to postgresql documentation.
If there are at least one characters with upper case while all other are in lower case (or vice versa) this
string should be escaped.

Note: This may make postgres support more case sensitive than normally is, but needs to be left in for backwards
compatibility.
Method is public so a subclass extension can override it to always return false.