数据库里面有个保存css的样式的地方：

{"logo":"images\/logo2.png","logoText":"","siteDescription":"","favIconImg":"","fontSizeSwitcher":"0","backToTop":"1","offCanvas":"1","JMoffCanvasWidth":"300px","offCanvasPosition":"right","comingSoon":"0","comingSoonDate":"06-12-2014","responsiveLayout":"1","DisableComponentDisplay":["470","650","651","652","653"],"layout":"default","JMbaseFontSize":"14px","bodyFontType":"0;bodyFontFamily","bodyFontFamily":"Tahoma, Geneva, Verdana, sans-serif","bodyGoogleWebFontUrl":"\/\/fonts.googleapis.com\/css?family=Roboto:400,300,300italic,500,700","bodyGoogleWebFontFamily":"'Roboto', sans-serif","JMtopmenuFontSize":"15px","djmenuFontType":"1;djmenuGoogleWebFontUrl;djmenuGoogleWebFontFamily","djmenuFontFamily":"Arial, Helvetica, sans-serif","djmenuGoogleWebFontUrl":"\/\/fonts.googleapis.com\/css?family=Roboto:400,300,300italic,500,700","djmenuGoogleWebFontFamily":"'Roboto', sans-serif","JMmoduleTitleFontSize":"22px","headingsFontType":"1;headingsGoogleWebFontUrl;headingsGoogleWebFontFamily","headingsFontFamily":"Arial, Helvetica, sans-serif","headingsGoogleWebFontUrl":"\/\/fonts.googleapis.com\/css?family=Roboto:400,300,300italic,500,700","headingsGoogleWebFontFamily":"'Roboto', sans-serif","JMarticleTitleFontSize":"32px","articlesFontType":"1;articlesGoogleWebFontUrl;articlesGoogleWebFontFamily","articlesFontFamily":"Arial, Helvetica, sans-serif","articlesGoogleWebFontUrl":"\/\/fonts.googleapis.com\/css?family=Roboto:400,300,300italic,500,700","articlesGoogleWebFontFamily":"'Roboto', sans-serif","advancedFontSize":"18px","advancedFontType":"0;advancedFontFamily","advancedFontFamily":"Arial, Helvetica, sans-serif","advancedGoogleWebFontUrl":"","advancedGoogleWebFontFamily":"","advancedSelectors":"","themermode":"0","themerlogin":"0","sourceMap":"0","codeInjection":"","cssCompress":"0","jsCompress":"0","htmlCompress":"0","skipCompress":"","facebookOpenGraph":"0","facebookOpenGraphAppID":"","config":"","JMcolorVersion":"#7abd9a","JMimagesDir":"scheme2","JMpageBackground":"#ffffff","JMbaseFontColor":"#858585","JMborder":"#f1f1f1","JMarticleTitleFontColor":"#454545","JMtopbarBackground":"#f8f8f8","JMtopbarFontColor":"#858585","JMbarBackground":"#ffffff","JMbarFontColor":"#858585","JMbarBorder":"#f1f1f1","JMmegamenuFontColor":"#444444","JMmegamenuSubmenuBackground":"#fafafa","JMmegamenuSubmenuFontColor":"#858585","JMmegamenuSubmenuBorder":"#f1f1f1","JMheaderBackground":"#f8f8f8","JMheaderFontColor":"#858585","JMheaderBorder":"#f1f1f1","JMheaderModuleTitleFontColor":"#444444","JMcopyrightBackground":"#373737","JMcopyrightFontColor":"#696969","JMmoduleTitleFontColor":"#444444","JMmoduleTitleBorder":"#f1f1f1","JMoffCanvasBackground":"#333333","JMoffCanvasFontColor":"#ffffff","JMmediatoolsDescriptionBackground":"#ffffff","JMmediatoolsDescriptionFontColor":"#5f5f5f"}

我想把其中的\/\/fonts.googleapis.com\/css?family=Roboto:400,300,300italic,500,700 去掉
用replace怎么会报错呢
update table1 set params=replace(params,'\/\/fonts.googleapis.com\/css?family=Roboto:400,300,300italic,500,700','')