Types of SQL Statements
在开发中,我们会遇到下面的情形,在PL/SQL程序中定义了type类型的集合,当引用的时候出现PLS-00642错误: PLS-00642: local collection types not allowed in SQL statements 举例: SQL>DECLARE2TYPE idISTABLEOFNUMBER;3v_id id :=id(649605799,649605800,649605801,649605802);4BEGIN5FORrecIN(SELECTcolumn_value id...
SQL injection attack is that where a malicious person executes some invalid or threat SQL statements to control a web application database server of an attacker. It is normally used to change, append, or delete the contents in the database without his or her knowledge. Thereby, ...
A LONGTEXT field is always stored in the Unicode representation format. If the data type name TEXT is used without specifying the optional length, a LONGTEXT field is created. This enables CREATE TABLE statements to be written that will yield data types consistent with Microsoft SQL Server. A ...
CHAR is shorthand for CHARACTER. NATIONAL CHAR (or its equivalent short form, NCHAR) is the standard SQL way to define that a CHAR column should use some predefined character set. MySQL uses utf8mb3 as this predefined character set.
Now, let’s write 2 simple SQL SELECT statements and check if this is really true: 1 2 3 4 5 SELECT* FROMcity; SELECT* FROMcustomer; We can easily notice few things: Not all cites were used (only these with ids 1, 3 and 4 were) ...
The CREATE INDEX syntax is used for creating SQL indexes database statements. CREATE INDEX index_name ON table_name (column1, column2, ...); Example: Consider the table EMP_Details we used in the above section. CREATE INDEX Dept
Using SQL_variant data type Using spatial data types User defined types Configuring how java.sql.Time values are sent Programming with SQLXML Supporting XML data SQLXML interface Using statements with SQL Statements with stored procedures Using table-valued parameters ...
[MS-TSQLISO02]: SQL Server Transact-SQL ISO/IEC 9075-2 Standards Support Document 1 Introduction 2 Standards Support Statements 2 Standards Support Statements 2.1 Normative Variations 2.1 Normative Variations 2.1.1 Mandatory Features 2.1.2 Optional Features 2.1.2 Optional Features 2.1.2.1 B...
[ <scope clause> ] ... <collection type> ::= <array type> | <multiset type> ... <multiset type> ::= <data type> MULTISET ... Conformance Rules Without Feature S274, "Multisets of reference types", conforming SQL language shall not contain a <multiset type> that is based on a ...