给选定的列指定别名,如SELECT name as alias_name FROM ... 用反引号包裹列名或限定表名,如SELECT `name`, `t1`.`age` FROM t1 运算表达式,如SELECT 1+1, age+10 FROM ... 对列值做运算的函数,如SELECT CONCAT(last_name,', ',first_name) FROM ... 关键字ALL/DISTINCT限定是否返回重复行 ,默认...
SELECT*FROM TAB WHERE TAB.NAME='A' 其中的“FROM...WHERE”便是一个条件子句,其实SQL的语法并不难,您只需记住这样的一个规则,相信可以很快的了解SQL用法。 SQL语法与命令 SELECT语句 SELECT[predicate]{*|table.*|[table.]field [,[table.]field2[,...]]} [AS alias1 [,alias2[,...]]] FROM t...
BasicSELECTstatement基本的select语句 The basicsyntax for aSELECT statement is presented below. SELECT语句的基本语法如下。 |:多选一 []:可选择的内容 {}:多选一 没有被{}括起来的是必选 SELECT [DISTINCT |ALL] {* | select_list} FROM {table_name [alias] | view_name} [{table_name [alias] |...
35 Data Warehouse Service SQL Syntax 4 Data Types Column Description INTEGER BINARY_IN TEGER BIGINT Typical choice for integer, also called INT4 INTEGER alias, compatible with Oracle Big integer, also called INT8 Storag e Space Range 4 bytes -2,147,483,648 ~ +2,147,483,647 4 bytes -2...
statementselectusagedetailed)SQLstatementselectusagedetailedSELECT-SQLcommanddetailedSelect-SQLcommandRetrievedatafromoneormoretables.grammarSELECT[ALLDISTINCT][TOPnExpr[PERCENT]]|[Alias.]Select_Item[ASColumn_Name][[Alias.],Select_Item,[AS,Column_Name]...]FROM[FORCE][DatabaseName!]Table[[AS]Local_Alias...
EXECUTE statement;将特定于 DBMS 的 SQL 语句发送到 SAS 接口支持的 DBMS。 CREATE statement;通过create index在列上边创建索引,通过create table/view创建表格/视图。 DROP statement;删除表、视图或索引。 SELECT statement; 从表和视图中选择数据的列和行。
mysql> SELECT SLEEP(5); 相反,尝试一下DO语句的神奇: mysql> DO SLEEP(5); 以上例子适用于禁止产生结果集的存储函数或触发器。 2.3HANDLER语法 HANDLER tbl_name OPEN [ AS alias ] HANDLER tbl_name READ index_name { = | >= | <= | < } (value1,value2,...) ...
A.字符级的比较:当前被执行的语句和共享池中的语句必须完全相同.例如: SELECT * FROM EMP; 和下列每一个都不同 SELECT * from EMP;Select * From Emp;SELECT * FROM EMP; B.两个语句所指的对象必须完全相同 C.两个SQL语句中必须使用相同的名字的绑定变量(bind variables)例如:第一组的两个SQL语句是相同的...
SQL - The SQL SELECT Statement - SQL is a comprehensive database language. SQL, pronounced Sequel or simply S-Q-L, is a computer programming language used for querying relational databases following a nonprocedural approach. When you extract information
RangeVar*)($stmt->fromClause->head.data->ptr_value)(gdb) p *$fromclause$103 = {type = T_RangeVar, catalogname = 0x0, schemaname = 0x0, relname = 0x7f5ffa43d848 "item", partitionname = 0x0, subpartitionname = 0x0, inhOpt = INH_DEFAULT, relpersistence = 112 'p', alias = ...