MyString = String(5, 42) ' 返回 "***" MyString = String(10, "ABC") ' 返回 "AAAAAAAAAA" End Sub 如果参数number包含Null,则返回Null;如果参数character包含Null,则返回Null;参数character可以指定为字符串或者是ANSI字符代码,如: strString1=String(128,”=”) ‘用”=”填充 strString2...
The first component in the function above is the column or string to be picked apart. The second component is the delimiter. The third is the number of elements to return, counting from the left. If we want to grab the last two elements, we would use a negative two to instruct MariaD...
public static string SqlitePath; static DBContext() { MsSqlConn = AppConfigHelper.GetAppConfig("MssqlConnectionString"); SqliteConn = AppConfigHelper.GetAppConfig("SqliteConnectionString"); MySqlConn = AppConfigHelper.GetAppConfig("MySqlConnectionString"); SqlitePath = @"DataSource=" + GetCurrentP...
Note that if a string column is being compared with a numeric value, MariaDB will not use the index on the column, as there are numerous alternatives that may evaluate as equal (see examples below). Comparison Examples Converting a string to a number: ...
Literals (Constants) String, number, date, time, boolean literals Declaring Variables Declare variables within stored programs Loops and Conditional Statements LOOP statement, IF-THEN-ELSE and others AUTO_INCREMENT (Sequences) Create a sequence of numbers using the AUTO_INCREMENT attribute Comments withi...
17967007152-32809666989-26174672567-29883439075-95767161284-94957565003-35708767253-53935174705-16168070783' /* STRING(480) meta=61152 nullable=0 is_null=0 */ ### @4='34551750492-67990399350-81179284955-79299808058-21257255869' /* STRING(240) meta=65264 nullable=0 is_null=0 */ # Number of rows: 1...
实际该变量是把gtid_binlog_pos合并到gtid_slave_pos中,如果同一个server_id在gtid_slave_pos,且gtid_binlog_pos的sequence number,就使用gtid_binlog_pos的值。否则就用gtid_slave_pos。 uchar * Sys_var_gtid_current_pos::global_value_ptr(THD *thd, const LEX_CSTRING *base) { String str; char *p...
If the host nameisnot provided, itisassumed to be'%'. User names must match exactly, includingcase. You can use the emptystringto allow a user with any user name. 建! MariaDB [mysql]> create user'gnucash'@'localhost'identified by'xxxxyyy'->; ...
说明:假如expr1 不为NULL,则 IFNULL() 的返回值为expr1; 否则其返回值为 expr2。IFNULL()的返回值是数字或是字符串,具体情况取决于其所使用的语境。 注意:默认结果值为两个表达式中更加“通用”的一个,顺序为STRING、 REAL或 INTEGER。 例子:
else ui->txtsizeE->setText(QString::number(size)+"字节"); ui->txtnameE->setText(info.fileName()); //显示文件名 QDateTime created = info.created(); //定义一个时间对象 ui->createtimeE->setText(created.toString("yyyy-MM-dd hh:mm:ss")); 修改时间显示格式 ...