1. Which of the following SQL statement is valid? a) SELECT DISTINCT * FROM Users; b) SELECT DISTINCT First_Name FROM Users; c) SELECT DISTINCT First_Name Last_Name FROM Users; 2. What's the result of the following query? SELECT DISTINCT Join_Date From Users; ...
TRANSACTION 27540, ACTIVE 19 sec inserting mysql tables in use 1, locked 1 LOCK WAIT 3 lock struct(s), heap size 1136, 2 row lock(s), undo log entries 1 MySQL thread id 23, OS thread handle 14896, query id 582 localhost ::1 root update insert into song_rank(songId,weight) values...
mysql tablesinuse1, locked1LOCK WAIT3lock struct(s), heap size1136,2row lock(s), undologentries1MySQL thread id23, OS thread handle14896, query id582localhost ::1rootupdateinsertintosong_rank(songId,weight)values(18,100)onduplicatekeyupdateweight=weight+1***(1) WAITINGFORTHIS LOCKTOBE GR...
java.sql.SQLException: Duplicate entry'1300'forkey 'PRIMARY'at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.readErrorPacket(AbstractQueryProtocol.java:1681) ~[mariadb-java-client-2.7.2.jar!/:na] at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.readPacket(AbstractQueryProtocol.ja...
could not insert:[bucket.userpropertysetBucketPropertySetItem#bucketpropertysetBucketPropertySetItem@a70067d3];SQL[];ViolationofPRIMARYKEYconstraint'PK_OS_PROPERTYENTRY314D4EA8'.Cannot insert duplicate keyinobject'OS_PROPERTYENTRY'.;nested exception is java.sql.SQLException:ViolationofPRIMARYKEYconstraint'PK...
逻辑上我们需要怎么写: result = mysql_query(‘select * from xxx where id = 1’);row = mysql_fetch_assoc( 但是这样写有两个问题...1、效率太差,每次执行都要执行2个sql 2、高并发的情况下数据会出问题,不能保证原子性 还好MySQL 为我们解决了这个问题:我们可以通过 ON DUPLICATE KEY UPDATE 达到以上...
SQL Server Selecting results from subquery [duplicate]You can useROW_NUMBERto order the records for...
SQL Server resource usage (CPU, Memory, Storage) and Configuration Slow query performance Security, Encryption, Auditing, Authorization Database Client Programming Integration Services (SSIS) Master Data Services Parallel Data Warehouse (APS) Reporting Services (SSRS) SQL Server on Linux Tools Product Up...
Execute the transfer TSQL script (in batches corresponding to each Staging Database) to move to a single Target database For each of the two scenarios (i.e. whether a Table's duplicates is based on all columns (1) or some columns (2)), I have a different transfer query. Here is...
Set-CMGlobalConditionActiveDirectoryQuery Set-CMGlobalConditionAssembly Set-CMGlobalConditionFile Set-CMGlobalConditionGeneral Set-CMGlobalConditionIisMetabase Set-CMGlobalConditionOmaUri Set-CMGlobalConditionRegistryKey Set-CMGlobalConditionRegistryValue Set-CMGlobalConditionScript Set-CMGlobalConditionSqlQuery Set...