E.g.: The requirement is to find out the count of employees for various conditions as given below. There are multiple ways of getting this output. Five different statements can be written to find the count of employees based on salary and commission conditions, or a single select having colu...
oracle.jdbc Interface OracleStatement All Superinterfaces: java.sql.Statement public interfaceOracleStatement extends java.sql.Statement Extended functionality includes support for settings flags and options for Oracle performance extensions on a statement-by-statements basis, as opposed to theOracleConnection...
如果在使用tkprof工具添加explain=username/passwd可一在文件中看到执行计划,如下: 下面的部分是对这个SQL_TRACE期间所有非递归SQL(NON-RECURSIVE STATEMENTS)的执行信息统计汇总 递归SQL: 执行一条SQL语句衍生出执行的一些其他的SQL,这些衍生出来的SQL就叫做递归SQL。 比如对SQL进行分析,需要读取一些数据字典来获取相关的...
All SELECT statements should use an explicit cursor. Implicit SELECT statements actually cause 2 fetches to execute: one to get the data, and one to check for the TOO_MANY_ROWS exception. You can avoid this by FETCHing just a single record from an explicit cursor. If you want to SELECT i...
types and objects into prepared statements, and methods to support Oracle performance extensions on a statement-by-statements basis. About prepared statements : To write changes to the database, such as for INSERT or UPDATE operations, you will typically create a PreparedStatement object. This allo...
statements, flushing, manual loading, manual refreshing, synchronous writethrough, and propagating. BothSQLQueryTimeoutandSQLQueryTimeoutMsecattributes are internally mapped to one timeout value in milliseconds. If different values are specified for these attributes, TimesTen retains the value specified by...
Statements are instructions that Oracle FastFormula carries out. There are six types of statement you can use:Alias statementAssignment statementDefault statementIf statementInputs statementReturn statement An If statement can have Assignment, Return, and other If statements nested within it, enabling you...
case.zip While CASE constructs don't offer any fundamentally new semantics, they do allow a more compact notation and some elimination of repetition with respect to what otherwise would be expressed with an IF construct.Using CASE Statements in PL/SQL programs ...
Single table, single column index, multiple statements Unique index (equality and range predicates) non-unique index covering unique constraint non-unique index generally Inlist iterator and union all. Nested loop joins Single table, Multi-column index (access/filter, and skip scan) Index-only qu...
To improve the optimization of SQL statements, Oracle introduced the cost-based optimizer in Oracle7. As the name implies, the cost-based optimizer does more than simply look at a set of optimization rules; instead, it selects the execution path that requires the least number of logical I/O...