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Confusion between prepared statement and parameterized query in Python

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As far as I understand, prepared statements are (mainly) a database feature that allows you to separate parameters from the code that uses such parameters. Example: PREPARE fooplan (int, text, bool, numeric) AS INSERT INTO foo VALUES($1, $2, $3, $4); EXECUTE fooplan(1, 'Hunter Valley', 't', 200.00); A parameterized query substitutes the manual string interpolation, so instead of doing cursor.execute("SELECT FROM tablename WHERE fieldname = %s" % value) we can do cursor.execute("SELECT FROM tablename WHERE fieldname = %s", [value]) Now, it seems that prepared statements are, for the most part,

JPA (Hibernate) Native Query for Prepared Statement SLOW

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Having strange performance issue using Hibernate 3.3.2GA behind JPA (and the rest of the Hibernate packages included in JBoss 5.) I'm using Native Query, and assembling SQL into a prepared statement. EntityManager em = getEntityManager(MY_DS); final Query query = em.createNativeQuery(fullSql, entity.getClass()); The SQL has a lot of joins, but is actually very basic, with a single parameter. Like: SELECT field1, field2, field3 FROM entity left join entity2 on... left join entity3 on WHERE stringId like ? and the query runs in under a second on MSSQL Studio. If I add query.setParameter(0,

Prepared Statement vs. Stored Procedure

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If you are using php5 and mysql5, is there a substantial advantage to using stored procs over prepared statements? ( i read somewhere you may not get substantial performance gains from mysql5 stored proc) They are not really the same thing - with stored procedures, your database logic resides inside the database. Prepared statements basically avoid re-parsing queries if they are called multiple times - the performance benefit can vary greatly. The choice to use one or the other is really dependent on your specific situation. I don't really use stored procs anymore as I like having all of my

JDBC - How to set char in a prepared statement

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I cannot find any method like char c = 'c'; preparedStatement.setChar(1, c); How to set character to a prepared statement? The JDBC Specification 4.0 in Appendix B (Data Type Conversion Tables) states the following conversions: This table also shows the conversions used by the SQLInput reader methods, except that they use only the recommended conversions. JDBC Type Java Type ------------------------------------------- CHAR String VARCHAR String LONGVARCHAR String NUMERIC java.math.BigDecimal DECIMAL java.math.BigDecimal BIT boolean BOOLEAN boolean TINYINT byte SMALLINT short TABLE B- 1 JDBC

INSERT several rows with a prepared statement in a loop

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问题 Sqlserv php error when inserting using array portion ARRAY PREPRATION foreach ($data as $rs) { $params []="({$rs->hd},'{$rs->dvn}',{$rs->mth},{$rs->yr},{$rs->stid},{$rs->prcd},'{$rs->prnm}',{$rs->prte},{$rs->ssl},{$rs->clsk},1)"; } INSERT INTO STATEMENT: $SqlInsert="insert into SQl_test (Ss_Hq_cd,Ss_division,Ss_month,Ss_yr,Ss_stk_Id,Ss_prod_cod,Ss_prod_name,ss_prod_rate,Ss_Sale,Ss_Cl_stk,ss_tran_stat) values(?,?,?,?,?,?,?,?,?,?,?) "; $stmt = sqlsrv_query( $conn, $SqlInsert,$params); EROOR:

MySqli prepare statement error when used for LIKE

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问题 I'm trying to make a prepared statement for a LIKE query using php's mysqli extension. But no matter what I try, I always get this error: Fatal error: Problem preparing query (SELECT f.*,r.slug FROM `foods` AS f INNER JOIN `resturants` AS r ON f.`rest_id` = r.`rest_id` WHERE f.`name` LIKE CONCAT('%',"f", '%')) You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''%',"f", '%')' at line 4 in /path/to/class.mysqli

PHP PDO Mysql Insert Performance

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问题 I normally don't use a lot of SQL stuff in PHP but recently have been forced into it by a friend as to help him debug something. I am using PDO with PHP to insert some data but the insert performance is abysmal. A simple loop of 151 inserts takes nearly 6 seconds! and I am lost as to why. Here is my code: <?php $database='XXXXXX'; $username='XXXXXX'; $password='XXXXXX'; $hostname='127.0.0.1'; $inserted=0; $counted=0; $dsn = 'mysql:dbname='.$database.';host='.$hostname.''; $start=microtime

php - How to parametrize SQL query with multiple WHERE conditions (prepared statement)?

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问题 I have multiple conditions in WHERE clause which are inputted by user (call them filters ). Currently I am processing them this way (don't worry it isn't deployed): //$by_nickname etc. are filters from $_GET $conditions = array(); if($by_nickname !="") { $conditions[] = " players.lastName LIKE ('%" . $by_nickname . "%')"; } if($by_steamid !="") { $conditions[] = " ids.uniqueId = '$by_steamid'"; } if($by_ip !="") { $conditions[] = " players.lastAddress = '$by_ip'"; } if($by_msg !="") {

Fatal error: Call to undefined method mysqli_stmt::query()

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问题 Hey guys, can any of you find out why I'm getting the above error? $mysqli=new mysqli("localhost", "***", "***","***") or die($mysqli->connect_error); function checklogin($username, $password){ global $mysqli; $result = $mysqli->prepare("SELECT * FROM users WHERE username = ?"); $result->bind_param("s", $username); $result->query(); 回答1: Calling $mysqli->prepare() will return an instance of MySQLi_STMT , but the MySQLi_STMT class doesn't have a query() method. Perhaps you meant execute()? 来源：

Missing STOPKEY per partition in Oracle plan for paging by local index

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There is next partitioned table: CREATE TABLE "ERMB_LOG_TEST_BF"."OUT_SMS"( "TRX_ID" NUMBER(19,0) NOT NULL ENABLE, "CREATE_TS" TIMESTAMP (3) DEFAULT systimestamp NOT NULL ENABLE, /* other fields... */ ) PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 STORAGE(BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "ERMB_LOG_TEST_BF" PARTITION BY RANGE ("TRX_ID") INTERVAL (281474976710656) (PARTITION "SYS_P1358" VALUES LESS THAN (59109745109237760) SEGMENT CREATION IMMEDIATE PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE(INITIAL 8388608 NEXT 1048576