convert oracle sql to postgresql

). Nvachr in SQL Server should also use utf16le, while nvarchar2 in Oracle uses utf16be, which leads to inconsistent MD5 value strings! The output values of qaz123 are: ORACLE: View plain Copy to clipboard Print ? SQL> select utl_raw.cast_to_varchar2 (utl_encode.base64_encode (get_md5 ('qaz123 ') from dual; Utl

dept table contains the following columns:Dept_code PK not nullDept_desc not nullDept_type nullInefficiency: (indexes are not used)Select dept_code from Dept order by dept_typeEfficiency: (using indexes)Select dept_code from Dept where dept_type> 0(30) Avoid changing the index column type .:Oracle automatically converts columns to different types of data.Assume that empno is a numeric index column.Select... From EMP where empno = '20140901'In fact, a

): utl_inaddr.get_host_address client: sys_context ('userenv', 'IP _ address ')[Q] How to encrypt the Stored Procedure[A] use the wrap command, for example (assume that your stored procedure is saved as. SQL) wrap iname =. sqlPL/SQL Wrapper: Release 8.1.7.0.0-Production on Tue Nov 27 22:26:48 2001 Copyright (c) Oracle Corporation 1993,200 0. all Rights Reserved.

the optimizer. This allows the optimizer to select a query execution plan that minimizes the response time, to quickly generate the first n rows of the query results. This parameter is newly introduced by Oracle 9i. Since Oracle V7, the default optimizer_mode parameter should be set to "choose", that is, if you select CBO for the analyzed Table query, otherwise select RBO. In this setting, if CBO is used,

indexes)Select dept_code from Dept where dept_type> 0 (30) Avoid changing the index column type .: Oracle automatically converts columns to different types of data.Assume that empno is a numeric index column.Select... From EMP where empno = '20140901'In fact, after Oracle type conversion, the statement is converted:Select... From EMP where empno = to_number ('123 ')Fortunately, the type conversion does no

clause: Oracle will convert ' * ' to all column names in the process of parsing, which is done by querying the data dictionary, which means it will take more time to (4) Reduce the number of times to access the database: Oracle does a lot of work internally: Parse SQL statements, estimate index utilization, bind

, with an optional numeric format. SQL Server returns character data after a numeric conversion through the STR function. However, the function does not have a convenient format parameter. Oracle queries are as follows:SELECT To_char (123.45, 99999999999999) from tabSELECT to_char (expiry_date, ' ddmonyyyy ') from tab The following is a SQL Server version of the

these complementary features. This article describes the most common and non-standard Oracle extensions. It also describes how to convert these extensions for use in the SQL Server environment.　　Column SelectionWhen PLSQL is used to perform data queries, the FROM clause is required, which is the same as that of SQL Se

Article Author: kj021320 Source of information: Evil Octal Information Security team (www.eviloctal.com) Note: This article starts I.S.T.O technical team, after the original creator friendship submits to the evil Octal information Security Team Forum. author:kj021320 Team:i.s.t.o A lot of people say what ASP PHP JSP injection In fact, the most direct injection is related to the database! However, those scripts are just an auxiliary For example, the asp/aspx JSP has no restrictions! and PHP will

(1)Select the most efficient table name order (only valid in the rule-based optimizer): The Oracle parser processes the table name from the FROM clause in a right-to-left order, and the last table written in the FROM clause (base table driving tables) is processed first. In cases where the FROM clause contains more than one table, you must select the table with the lowest number of record bars as the underlying table. If you have more than 3 tables co

Kindles blog Many people say that asp php jsp injection is most directly related to databases! However, those scripts are only a helper.For example, ASP/aspx jsp has no restrictions! However, PHP will filter it out, but if it is not mysql postgresql sqlite, this function will be useless!However, I don't think these scripting languages are harsh ~ If CFM is used, it is estimated that you will not lose the discount! For more information about each datab

');Values time (' 22:45:27 ');Values time (' 22.45.27 ');--Calculates the difference between two time stamps:-The number of seconds is divided into unitsValues Timestampdiff (1,char (current timestamp-timestamp (' 2010-01-01-00.00.00 ')); --Unit of secondsValues Timestampdiff (2,char (current timestamp-timestamp (' 2010-01-01-00.00.00 ')); --Divided into unitsValues Timestampdiff (4,char (current timestamp-timestamp (' 2010-01-01-00.00.00 ')); --Hour unitValues Timestampdiff (8,char (current ti

, this example is "billingserver"; 15). Execute the "Convert Schema" in the "Oracle Metadata Explorer" window; 16). Execute "Synchronize with Database" in the SQL Server Metadata Explorer window; 17). Confirm the library structure information to be synchronized; After the successful execution of the "Synchronize with Database", the target database structure i

Second, SQL structur Query Language Structured Query language, is the object in the Operation relational database.DDL (data definition Language), used to create or delete table operations, and to modify table constraints CREATE TABLE, ALTER TABLE, DROP table additions and deletions to tables structure. DML (Data manipulation language), inserting records into tables, modifying records INSERT, UPDATE, delete, merge transaction, transaction control langu

you can limit the number of records through the WHERE clause, you can reduce this overhead.Optimization techniques for SQL (6)Conditional use of Union-all instead of union: This will increase the efficiency by 3 to 5 times times.Optimization techniques for SQL (7)In the SQL statement that contains the subquery, pay special attention to reducing the query on the

From: http://dev.csdn.net/article/56/56449.shtm T-SQL is the language engine of SQL Server, while Oracle's language engine is PLSQL. Both query languages have extended the ANSI SQL-92 standard to provide additional support. Almost all applications you create use these complementary features. This article describes the most common and non-standard

T-SQL is the language engine of SQL Server, while Oracle's language engine is PLSQL. Both query languages have extended the ANSI SQL-92 standard to provide additional support. The application you createdProgramAlmost all of these complementary features are used. This article describes the most common and non-standard Oracle