Oracle 10g SQL Fundamentals II(学习笔记二第7-8章)
第七章分层检索语法：SELECT [LEVEL], column, expr...FROM table[WHERE condition(s)][START WITH condition(s)][CONNECT BY PRIOR condition(s)] ; 例如：SELECT employee_id, last_name, job_id, manager_idFROM employeesSTART WITH employee_id = 101CONNECT BY PRIOR manager_id = employee_id ;SELECT last_name||' reports to '|| PRIOR last_name "Walk Top Down"FROM employeesSTART WITH last_name = 'King'CONNECT BY PRIOR employee_id = manager_id ;第八章，正则表达式支持REGEXP_LIKE:语法：REGEXP_LIKE (srcstr, pattern [,match_option]) 例如： SELECT first_name, last_nameFROM employeesWHERE REGEXP_LIKE (first_name, '^Ste(v|ph)en$');REGEXP_REPLACE 语法：REGEXP_REPLACE(srcstr, pattern [,replacestr [, position [, occurrence [, match_option]]]]) REGEXP_INSTR语法：REGEXP_INSTR (srcstr, pattern [, position [, occurrence[, return_option [, match_option]]]]) 例如： SELECT street_address, REGEXP_INSTR(street_address,'[^[:alpha:]]')FROM locations WHERE REGEXP_INSTR(street_address,'[^[:alpha:]]')> 1;REGEXP_SUBSTR语法： REGEXP_SUBSTR (srcstr, pattern [, position [, occurrence [, match_option]]]) 例如： SELECT REGEXP_SUBSTR(street_address , ' [^ ]+ ') "Road" FROM locations; 添加一个检查约束： ALTER TABLE emp8 ADD CONSTRAINT email_addr CHECK(REGEXP_LIKE(email,'@'))NOVALIDATE ;
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