Select
Select returns the order of records
Zhongxing Communication Chongqing Institute Rempo Wu Yuhong
Keywords: SELECT, order, optimize, backup, scan, index
Article Summary:
When we execute the SELECT statement, the order of the records
Insert 10000 records, insert 20000 records in 0 seconds, insert 30000 records in 2 seconds, insert 40000 records in 3 seconds, and insert 50000 records in 3 seconds, 60000 messages are inserted in 4 seconds, 70000 messages are inserted in 5 seconds,
In the practical application, often need to implement in a query statement to display more than one table of data, this is called a multiple table data record connection query, referred to the next year will be the query.
When you implement a
The most common operation of database is "plug, check, delete, change". In the previous log, I introduced the MySQL inserts INSERT statement, also introduced the update UPDATE statement for everyone, as well as deletes the statement delete and the
Oracle queries the first 10 records and paging queries (5th to 10th records), and oracle queries the first 10 records
If you want to know the actual application solutions of the first 10 records in Oracle query, you can click the following article
The SQL statement I used:
Delete from fp_sgfpxxWhere fphm in (select fphm from fp_sgfpxx group by fphm having count (fphm)> 1)And rowid not in (select min (rowid) from fp_sgfpxx group by fphm having count (fphm)> 1)
Delete duplicate invoice
Search for records with all repeated titles :? 1SELECT * FROMt_infoaWHERE (SELECTCOUNT (*) FROMt_infoWHERETitlea.Title) 1) ORDERBYTitleDESC 1. Search for duplicate records 1. Search for all duplicate records? 1Select * From table Where repeated
SQL statement + select top usage of "Fetch 10th to 20th records from a data table", 10th SQL statements
1. First, select top usage:
For more information, see the differences between select top n * from and select * from.
Select * from table --
Set of records
As mentioned earlier, it is not surprising that the recordset is the most commonly used object in ADO. After all, they contain the data. However, there is more to the recordset than you can imagine, and it is important to know how the
1. After testing, the following method is passed:
Select * from(Select Table name. *, rownum as con from table name where rownum )Where con> = N;
2. Refer to other online methods
SQL/Oracle Method for retrieving records from MB to
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