This PR adds the processing of lowercase Column names in Oracle Jdbc Catalog. In the previous behavior, we changed all Oracle columns to uppercase queries by default, but could not handle the lowercase case. This PR can solve this situation and improve All Jdbc Catalog works
The changes of this PR for JdbcOracleClient are as follows:
#### bug fixes:
1. Fix the problem that if there is an approximate table name for Schema synchronization with a table name with `/` characters, the synchronization Column will be confused
2. Fix the NPE problem of metadata synchronization after enabling lower_case_table_names configuration
#### improvement:
1. Modify the method of synchronizing Oracle User to Doris Database mapping, use `metadata.getSchemas` instead of `SELECT DISTINCT OWNER FROM all_tables`
2. When synchronizing metadata, change `null` at the catalog level to `conn.getcatalog`
The data type `NUMBER(p,s)` of oracle has some different of doris decimal type in semantics.
For Oracle Number(p,s) type：
1.
if s<0 , it means this is an Interger. This `NUMBER(p,s)` has (p+|s| ) significant digit,
and rounding will be performed at s position.
eg: if we insert 1234567 into `NUMBER(5,-2)` type, then the oracle will store 1234500. In this case,
Doris will use
int type (`TINYINT/SMALLINT/INT/.../LARGEINT`).
2. if s>=0 && s<p , it just like doris Decimal(p,s) behavior.
3. if s>=0 && s>p, it means this is a decimal(like 0.xxxxx).
p represents how many digits can be left to the left after the decimal point,
the figure after the decimal point s will be rounded. eg: we can not insert 0.0123456 into `NUMBER(5,7)` type,
because there must be two zeros on the right side of the decimal point,
we can insert 0.0012345 into `NUMBER(5,7)` type. In this case, Doris will use `DECIMAL(s,s)`
4. if we don't specify p and s for `NUMBER(p,s)` like `NUMBER`,
the p and s of `NUMBER` are uncertain. In this case, doris can not determine p and s,
so doris can not determine data type.
