smf records

The distinct (STR) function is used to remove duplicate records, but it is only possible to repeat for a certain field. For example: SELECT DISTINCT (name) from TableName; However, if you want to query the records of other field values, I started thinking about using select DISTINCT (name), ta.* from TableName. Note that distinct must be placed in front! But this did not remove the duplicate

PL/SQL RecordsPL/SQL records are data structures that can accommodate different types of data items. Records are made from different fields, similar to rows in a database table.For example, to keep track of books in libraries. You may want to track the following properties for each book similar to: title, author, subject, book ID. Contains a field for each of these item

Sharing: 10 PCs with 0.2 billion million data records can be queried in less than 0.3 seconds. It takes only 3 minutes to insert 6.5 million data records. Open-source: the programmable distributed cloud platform (bdc2.0) for millions of business circles is officially released.---- 10 PCs with 0.3 million data records can be queried in less than secondsQuery

C # program A sends log records to program B, program B processes and parses log recordsKeywords: C #; Log record; online log record; Socket;httplistenerFirst, the common scene1, app development, in the real machine or virtual machine run by H5 or Apicloud program, or debugging someone else to write the program, often can not see a piece of code after the output of the implementation of what. As a person to deal with the background every day, the brow

Select * from table1 Select * from table2 Select a. *, B. * from table1 a, table2 B where a. id = B. e -- Query if column X of Table 1 has repeated values, take only oneSelect min (id) as id, B, c from table1 group by B, c order by id asc -- 1. Search for redundant duplicate records in the Table. duplicate records are determined based on a single field (peopleId ).Select * from table1 where B in (se

PLSQL defines record records and plsqlrecord records 1. Basic use of PLSQL Note: 1. Three paragraphs declare Begin Exception End; 2. Declaration: emp. ename % type; is the same as the attribute of the field. 3. begin: select stores variables with query automatic. 4. Condition Statement: (1) if then Statement; End if; (2) When then Statement; Declare V_ename emp. ename % type; E_meet_scott exception; Begin

Use Red envelopes query record interface, after July 13 records still can query, but before the return said "query number corresponding data does not exist, please use the correct merchant order numbers query", but in the merchant number is the corresponding order number, is this query record is time period limit? How many days ago can I query for records or something like that? Reply content: Use Red

Trainer sub-project (4) security guard-blacklist interception using content providers to delete call records and provider call recordsIn the previous section, we talked about deleting a call record, but a bug is that it will first appear in the call record, and then disappear, which is not good for the user experience, therefore, we need to use the content provider to observe the changes in the call records

IOS learning 4. Storing chat records and ios storing chat records It mainly uses sqlite3 to store chat records Import sqlite3.dylib, click Add Other, and press shift + command + G to enter/Usr/lib/libsqlite3.dylibAnd then OK. Import 1. A new file Text class is used for storage, and. m does not require any operation. 1 # import 2. encapsulate another TextModel c

Liunx disk management Command records and liunx disk Command records Linux disk management is directly related to the performance of the entire system. Linux disk management commonly uses three commands: df, du, and fdisk. Df: list the total disk usage of the file system Du: Check disk space usage Fdisk: used for disk partitioning Today, let's talk about how to use the fdisk and parted partitioning to

When I use C # To save an access data, the system prompts that the data types are inconsistent. When data is stored An error occurred. "Microsoft Office Access cannot append all records in the append query. Microsoft Office Access Field 1 is set to null because of type conversion failure. It does not add 0 records to the table because of key-value conflicts. 0

SQL statements remove duplicate records, get duplicate records --Query a table to effectively remove duplicate records, UserID as a self-growing primary key, Roleid as a repeating field SELECT MIN (UserID) as UserID, Roleid from Tmptable GROUP by Roleid SELECT Roleid from Tmptable GROUP by Roleid (COUNT (*) > 1) SELECT DISTINCT * from tmptable SQL statement qu

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 field In (Select repeated field From Table Grou Search for records with all

Redis learning records and redis recordsRedis is a key-value storage system. Similar to Memcached, Memcached supports more storage value types, including string, list, set, and zset) and hash (hash type ). These data types support push/pop, add/remove, Intersection Set and difference set, and more abundant operations, and these operations are atomic. On this basis, redis supports sorting in different ways. Like memcached, data is cached in the memory

Linux learning records. 1. Installation, linux learning records. 1 I recently thought about how to start learning linux. After Baidu started the installation, the virtual machine VirtualBox and ubuntu.Ubuntu text tutorial Based on VirtualBox virtual machine: Http://blog.csdn.net/u012732259/article/details/70172704 Install the enhancement feature and start using it. Use the ingenious Linux Command learn

SymmetricDS installation records and metrics ricds records This installation record is based on the example in the getting ricds Quick Start Guide and installed on two machines.Installation environment Machine1: hadoop3.highgo.com Machine2: hadoop4.highgo.comInstall javasricds 1. Download The ricdsserver program and download the ric-3.6.14 file. Decompress the package to the/opt/directory of the two machine

SQL queries today's records: Datediff (day, [datetime], getdate () = 0 replace datetime with your corresponding field; SQL query records of yesterday: Datediff (day, [datetime], getdate () = 1 replace datetime with your corresponding field. getdate ()-datetime is the time difference. This month's record: Select * from table where datediff (month, [dateadd], getdate () = 0 Weekly record: Select

C ++ learning records and learning records Recently, Arduino found that C ++ is used when writing function libraries. I had a textbook on hand, so I started to study again after two years. It seems a little excited to reload, construct, and copy these words. Start a series of logs to record the problems and experiences in the learning process. When I saw the input and output, I thought of C ++'s compatibil

Linux environment deployment records (3) and linux environment deployment records Install Jenkins To be compatible with the jdk1.7 production environment, we know from the official website that Jenkins must be a version earlier than 1.6, So download the jenkins-1.596.3-1.1.noarch.rpm to local installation: # Move to rpm package directory rpm-ivh jenkins-1.596.3-1.1.noarch.rpm After the installation, modif

How do I randomly select n records or randomly sort records ?. Q. How do I obtain random sorting results? A. You can use random numbers to obtain columns in random sorting or return x randomly selected columns. However, the RAND function returns only one Q in a query. how do I obtain the random sorting result? A. You can use random numbers to obtain columns in random sorting or return x randomly selected co