#How to install sap download manager in windows 8 update
UPDATE class101 SET gpa = gpa + 1.0 WHERE name = 'Tan Ah Teck' - Selected rows CREATE TABLE - SYNTAX CREATE TABLE tableName ( column1Name column1Type, column2Name column2Type. Missing fields will be set to their default values or NULL UPDATE - SYNTAX UPDATE tableName SET column = value WHERE criteria - EXAMPLES INSERT INTO class101 (name, gpa) VALUES ('Peter Jones', 4.55) INSERT INTO class101 VALUES (1001, 'Tan Ah Teck', 4.5) , lastColumnValue) - All columns INSERT INTO tableName ( column1, column2. INSERT - SYNTAX INSERT INTO tableName VALUES ( firstColumnValue. Delete ALL rows from the table class101! Beware that there is NO UNDO! +-+-+-+ DELETE - SYNTAX DELETE FROM tableName WHERE criteria - EXAMPLES If two rows have the same gpa, order by name in ascending order. Order the result by gpa in descending order. SELECT * FROM class101 WHERE gpa > 4 AND name LIKE 'k%' ORDER BY gpa DESC, name ASC - Use AND, OR, NOT to combine simple conditions. wildcard _ matches one (any) character. wildcard % matches zero or more (any) characters SELECT name FROM class101 WHERE name LIKE 'k%' - Use "LIKE" to perform pattern-matching on strings, with SELECT name, gpa FROM class101 WHERE name = 'Tan Ah Teck' - Perform FULL-match on strings (= or !=). You can compare numbers (INT, FLOAT) using =, >, =, (!=) SELECT name, gpa FROM class101 WHERE gpa >= 4.7 - Select columns name and gpa from table class101, where the rows meet the criterion (gpa >= 4.7). The wildcard * denotes all the columns. SELECT * FROM class101 - Select ALL columns from table class101. FROM tableName WHERE criteria SELECT * FROM tableName WHERE criteria - EXAMPLES SELECT name, gpa FROM class101 - Select columns name and gpa from table class101. SQL (Structure Query Language) defines a set of intuitive commands (such as SELECT, INSERT, DELETE, UPDATE) to interact with relational database system. | id (INT) | name (VARCHAR(50)) | gpa (FLOAT) | We choose: INT (integer) for column id, VARCHAR(50) (variable-length string of up to 50 characters) for name, and FLOAT (floating-point number) for gpa. Suppose we have a database called studentdb, a table called class101 in the database with 3 columns ( id, name, gpa) and 4 rows as illustrated below. A table have rows (or records) and columns (or fields).A relational database system contains many databases.SQL By ExamplesĪ relational database system organizes data in the following hierarchy: However, most of the database vendors have their own directs, e.g., PL/SQL (Oracle), Transact-SQL (Microsoft, SAP), PL/pgSQL (PostgreSQL). SQL, one of the earlier programming language, was subsequently developed by Donald D.
Codd of IBM proposed the Relational Database Model in 1970.
SQL defines a set of commands, such as SELECT, INSERT, UPDATE, DELETE, CREATE TABLE, DROP TABLE, and etc.Įdgar F.
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