Most languages provide a way to do generic parameterized statements, Python is no different. When a parameterized query is used databases that support preparing statements will automatically do so. In python a parameterized query looks like this: cursor.execute(“SELECT FROM tablename WHERE fieldname = %s”, [value]) The specific style of parameterization may be different depending on … Read more
Stored procedures are a sequence of instructions in PL/SQL language. Is a programming language implemented by some DBMS, that lets you store sequences of queries frequently applied to your model, and share the processing load with the application layer. Prepared statements are queries written with placeholders instead of actual values. You write the query and … Read more
The notion that prepared statements are primarily about performance is something of a misconception, although it’s quite a common one. Another poster mentioned that he noted a speed improvement of about 20% in Oracle and SQL Server. I’ve noted a similar figure with MySQL. It turns out that parsing the query just isn’t such a … Read more
Yes. See here. Section 7.1.9. Change your code to: String sql = “INSERT INTO table (column1, column2) values(?, ?)”; stmt = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS); stmt.executeUpdate(); if(returnLastInsertId) { ResultSet rs = stmt.getGeneratedKeys(); rs.next(); auto_id = rs.getInt(1); }
❐ Using java.sql.Date If your table has a column of type DATE: java.lang.String The method java.sql.Date.valueOf(java.lang.String) received a string representing a date in the format yyyy-[m]m-[d]d. e.g.: ps.setDate(2, java.sql.Date.valueOf(“2013-09-04”)); java.util.Date Suppose you have a variable endDate of type java.util.Date, you make the conversion thus: ps.setDate(2, new java.sql.Date(endDate.getTime()); Current If you want to insert the current … Read more
This behaviour is quite annoying since JSON strings are accepted without problems when used as literal strings in SQL commands. There is a already an issue for this in the postgres driver Github repository (even if the problem seems the be the serverside processing). Besides using a cast (see answer of @a_horse_with_no_name) in the sql … Read more
If you use the string literal exactly as you have shown us, the problem is the ; character at the end. You may not include that in the query string in the JDBC calls. As you are inserting only a single row, a regular INSERT should be just fine even when inserting multiple rows. Using … Read more
What you are seeing is a parameterized query. They are frequently used when executing dynamic SQL from a program. For example, instead of writing this (note: pseudocode): ODBCCommand cmd = new ODBCCommand(“SELECT thingA FROM tableA WHERE thingB = 7”) result = cmd.Execute() You write this: ODBCCommand cmd = new ODBCCommand(“SELECT thingA FROM tableA WHERE thingB … Read more
Each method of mysqli can fail. Luckily, nowadays mysqli can report every problem to you, all you need is ask. Simply add this single line to the connection code, mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT); And after that every error will reveal itself. No need to test any return values ever, just write your statements right away: $stmt … Read more
Although both methods work with * queries, when bind_result() is used, the columns are usually listed explicitly in the query, so one can consult the list when assigning returned values in bind_result(), because the order of variables must strictly match the structure of the returned row. Example 1 for $query1 using bind_result() $query1 = ‘SELECT … Read more