First, let's look at the sample SQL statement to be parsed:
Copy codeThe Code is as follows: select * from dual
SELECT * frOm dual
Select C1, c2 From tb
Select c1, c2 from tb
Select count (*) from t1
Select c1, c2, c3 from t1 where condi1 = 1
Select
First look at the sample SQL statement to parse:
Copy Code code as follows:
SELECT * FROM dual
SELECT * from dual
Select C1,C2 from TB
Select C1,C2 from TB
Select COUNT (*) from T1
Select c1,c2,c3 from t1 where condi1=1
"Editor's note" the author of this article is Reinder de Vries, an entrepreneur and an excellent programmer, who publishes multiple application blogs. In this article, the author focuses on how to create an Instagram-like app based on the parse
Let's take a big picture first:Combine to illustrate the locks involved in each step of the resolution.A simple explanation of the difference between soft parsing, hard parsing and soft and soft parsing:To translate the user-written SQL text into
Each DDL execution requires hard parsing.
SQL parsing process
Oracle will take the following steps to process this SQL statement:
1. syntax check: Check whether the spelling of this SQL statement is correct.
2. semantic check: such as checking
Abstract: In the PLSQL development process, the use of SQL and PLSQL can meet most of the requirements, but in some special circumstances, using standard SQL statements or DML statements in PLSQL cannot meet your needs. for example, dynamic table
Abstract: In the PL/SQL development process, SQL, PL/SQL can be used to meet most of the requirements. However, in some special cases, standard SQL statements or DML statements in PL/SQL cannot meet your needs. For example, dynamic table creation or
SQL turning is a tool in the Quest Central software produced by Quest Corporation. Quest is an integrated, graphical, Cross-platform database management solution that can manage Oracle, DB2, and SQL Server databases simultaneously.
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